Search Results: "luk"

22 June 2022

John Goerzen: I Finally Found a Solid Debian Tablet: The Surface Go 2

I have been looking for a good tablet for Debian for well, years. I want thin, light, portable, excellent battery life, and a servicable keyboard. For a while, I tried a Lenovo Chromebook Duet. It meets the hardware requirements, well sort of. The problem is with performance and the OS. I can run Debian inside the ChromeOS Linux environment. That works, actually pretty well. But it is slow. Terribly, terribly, terribly slow. Emacs takes minutes to launch. apt-gets also do. It has barely enough RAM to keep its Chrome foundation happy, let alone a Linux environment also. But basically it is too slow to be servicable. Not just that, but I ran into assorted issues with having it tied to a Google account particularly being unable to login unless I had Internet access after an update. That and my growing concern over Google s privacy practices led me sort of write it off. I have a wonderful System76 Lemur Pro that I m very happy with. Plenty of RAM, a good compromise size between portability and screen size at 14.1 , and so forth. But a 10 goes-anywhere it s not. I spent quite a lot of time looking at thin-and-light convertible laptops of various configurations. Many of them were quite expensive, not as small as I wanted, or had dubious Linux support. To my surprise, I wound up buying a Surface Go 2 from the Microsoft store, along with the Type Cover. They had a pretty good deal on it since the Surface Go 3 is out; the highest-processor model of the Go 2 is roughly similar to the Go 3 in terms of performance. There is an excellent linux-surface project out there that provides very good support for most Surface devices, including the Go 2 and 3. I put Debian on it. I had a fair bit of hassle with EFI, and wound up putting rEFInd on it, which mostly solved those problems. (I did keep a Windows partition, and if it comes up for some reason, the easiest way to get it back to Debian is to use the Windows settings tool to reboot into advanced mode, and then select the appropriate EFI entry to boot from there.) Researching on-screen keyboards, it seemed like Gnome had the most mature. So I wound up with Gnome (my other systems are using KDE with tiling, but I figured I d try Gnome on it.) Almost everything worked without additional tweaking, the one exception being the cameras. The cameras on the Surfaces are a known point of trouble and I didn t bother to go to all the effort to get them working. With 8GB of RAM, I didn t put ZFS on it like I do on other systems. Performance is quite satisfactory, including for Rust development. Battery life runs about 10 hours with light use; less when running a lot of cargo builds, of course. The 1920 1280 screen is nice at 10.5 . Gnome with Wayland does a decent job of adjusting to this hi-res configuration. I took this as my only computer for a trip from the USA to Germany. It was a little small at times; though that was to be expected. It let me take a nicely small bag as a carryon, and being light, it was pleasant to carry around in airports. It served its purpose quite well. One downside is that it can t be powered by a phone charger like my Chromebook Duet can. However, I found a nice slim 65W Anker charger that could charge it and phones simultaneously that did the job well enough (I left the Microsoft charger with the proprietary connector at home). The Surface Go 2 maxes out at a 128GB SSD. That feels a bit constraining, especially since I kept Windows around. However, it also has a micro SD slot, so you can put LUKS and ext4 on that and use it as another filesystem. I popped a micro SD I had lying around into there and that felt a lot better storage-wise. I could also completely zap Windows, but that would leave no way to get firmware updates and I didn t really want to do that. Still, I don t use Windows and that could be an option also. All in all, I m pretty pleased with it. Around $600 for a fully-functional Debian tablet, with a keyboard is pretty nice. I had been hoping for months that the Pinetab would come back into stock, because I d much rather support a Linux hardware vendor, but for now I think the Surface Go series is the most solid option for a Linux tablet.

8 June 2022

Laura Arjona Reina: Moving to a faster but smaller disk, encrypted setup

My work computer runs Debian 11 bullseye (the current stable release) in a mechanical 500GB disk, and I was provided with a new SDD disk but its size was 480 GB. So I had to shrink my partitions before copying the data to the new disk. It turned out to be a bit difficult because my main partition was encrypted. I write here how I did, maybe there are other simpler ways but I couldn t find them. References: I had three partitions in my old 500GB disk: /dev/sda1 is the EFI partition, /dev/sda2 the boot partition and /dev/sda3 the root partition (encrypted, with LVM, the standard way the Debian installer proposes when you choose a simple encrypted setup). First of all, I made a disk image with Clonezilla to an external USB disk, just in case I mess up things, to be able to return to a safe point and start again. Then I started my computer with a Debian 11 live USB with KDE Plasma desktop and Spanish localisation environment. I opened the KDE Partition manager and copied the non encrypted partitions (sda1, EFI and sda2, /boot) to the new disk. I shrinked the encrypted partition from the terminal with the following commands (I had enough free space so reduced my partition to a total of 300GB): Removed the swap partition and re-created it:
sudo lvremove /dev/larjona-pc-vg/swap_1
sudo pvresize --setphysicalvolumesize 380G /dev/mapper/cryptdisk
sudo pvchange -x y /dev/mapper/cryptdisk
sudo lvcreate -L 4G -n swap_1 larjona-pc-vg
sudo mkswap -L swap_1 /dev/larjona-pc-vg/swap_1
Display information about the physical volume in order to shrink it:
sudo pvs -v --segments --units s /dev/mapper/cryptdisk
sudo cryptsetup -b 838860800 resize cryptdisk
sudo cryptsetup status cryptdisk
sudo vgchange -a n vgroup
sudo vgchange -an
sudo cryptsetup luksClose cryptdisk
Then reduced the sda3 partition with the KDE partition manager (it took a while), and copy it to the new disk. Turned off the computer and unplugged the old disk. Started the computer with the Debian 11 Live USB again, UEFI boot. Now, to make my system boot:
sudo cryptsetup luksOpen /dev/sda3 crypdisk
sudo vgscan --mknodes
sudo vgchange -ay
sudo mount /dev/mapper/larjona--pc--vg-root /mnt
sudo mount /dev/sda2 /mnt/boot
sudo mount /dev/sda1 /mnt/boot/efi
mount --rbind /sys /media/linux/sys
mount -t efivarfs none /sys/firmware/efi/efivars
for i in /dev /dev/pts /proc /run; do sudo mount -B $i /mnt$i; done
sudo chroot /mnt
Then edited /mnt/etc/crypttab to reflect the name of the new encrypted partition, edited /mnt/etc/fstab to paste the UUIDs of the new partitions.
Then ran grub-install and reinstalled the kernels as noted in the reference, rebooted and logged in my Plasma desktop  (Well, the actual process was not so smooth but after several tries and errors and searching for help I managed to get the needed commands to make my system boot from the new disk).

13 May 2022

Antoine Beaupr : BTRFS notes

I'm not a fan of BTRFS. This page serves as a reminder of why, but also a cheat sheet to figure out basic tasks in a BTRFS environment because those are not obvious to me, even after repeatedly having to deal with them. Content warning: there might be mentions of ZFS.

Stability concerns I'm worried about BTRFS stability, which has been historically ... changing. RAID-5 and RAID-6 are still marked unstable, for example. It's kind of a lucky guess whether your current kernel will behave properly with your planned workload. For example, in Linux 4.9, RAID-1 and RAID-10 were marked as "mostly OK" with a note that says:
Needs to be able to create two copies always. Can get stuck in irreversible read-only mode if only one copy can be made.
Even as of now, RAID-1 and RAID-10 has this note:
The simple redundancy RAID levels utilize different mirrors in a way that does not achieve the maximum performance. The logic can be improved so the reads will spread over the mirrors evenly or based on device congestion.
Granted, that's not a stability concern anymore, just performance. A reviewer of a draft of this article actually claimed that BTRFS only reads from one of the drives, which hopefully is inaccurate, but goes to show how confusing all this is. There are other warnings in the Debian wiki that are quite scary. Even the legendary Arch wiki has a warning on top of their BTRFS page, still. Even if those issues are now fixed, it can be hard to tell when they were fixed. There is a changelog by feature but it explicitly warns that it doesn't know "which kernel version it is considered mature enough for production use", so it's also useless for this. It would have been much better if BTRFS was released into the world only when those bugs were being completely fixed. Or that, at least, features were announced when they were stable, not just "we merged to mainline, good luck". Even now, we get mixed messages even in the official BTRFS documentation which says "The Btrfs code base is stable" (main page) while at the same time clearly stating unstable parts in the status page (currently RAID56). There are much harsher BTRFS critics than me out there so I will stop here, but let's just say that I feel a little uncomfortable trusting server data with full RAID arrays to BTRFS. But surely, for a workstation, things should just work smoothly... Right? Well, let's see the snags I hit.

My BTRFS test setup Before I go any further, I should probably clarify how I am testing BTRFS in the first place. The reason I tried BTRFS is that I was ... let's just say "strongly encouraged" by the LWN editors to install Fedora for the terminal emulators series. That, in turn, meant the setup was done with BTRFS, because that was somewhat the default in Fedora 27 (or did I want to experiment? I don't remember, it's been too long already). So Fedora was setup on my 1TB HDD and, with encryption, the partition table looks like this:
NAME                   MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                      8:0    0 931,5G  0 disk  
 sda1                   8:1    0   200M  0 part  /boot/efi
 sda2                   8:2    0     1G  0 part  /boot
 sda3                   8:3    0   7,8G  0 part  
   fedora_swap        253:5    0   7.8G  0 crypt [SWAP]
 sda4                   8:4    0 922,5G  0 part  
   fedora_crypt       253:4    0 922,5G  0 crypt /
(This might not entirely be accurate: I rebuilt this from the Debian side of things.) This is pretty straightforward, except for the swap partition: normally, I just treat swap like any other logical volume and create it in a logical volume. This is now just speculation, but I bet it was setup this way because "swap" support was only added in BTRFS 5.0. I fully expect BTRFS experts to yell at me now because this is an old setup and BTRFS is so much better now, but that's exactly the point here. That setup is not that old (2018? old? really?), and migrating to a new partition scheme isn't exactly practical right now. But let's move on to more practical considerations.

No builtin encryption BTRFS aims at replacing the entire mdadm, LVM, and ext4 stack with a single entity, and adding new features like deduplication, checksums and so on. Yet there is one feature it is critically missing: encryption. See, my typical stack is actually mdadm, LUKS, and then LVM and ext4. This is convenient because I have only a single volume to decrypt. If I were to use BTRFS on servers, I'd need to have one LUKS volume per-disk. For a simple RAID-1 array, that's not too bad: one extra key. But for large RAID-10 arrays, this gets really unwieldy. The obvious BTRFS alternative, ZFS, supports encryption out of the box and mixes it above the disks so you only have one passphrase to enter. The main downside of ZFS encryption is that it happens above the "pool" level so you can typically see filesystem names (and possibly snapshots, depending on how it is built), which is not the case with a more traditional stack.

Subvolumes, filesystems, and devices I find BTRFS's architecture to be utterly confusing. In the traditional LVM stack (which is itself kind of confusing if you're new to that stuff), you have those layers:
  • disks: let's say /dev/nvme0n1 and nvme1n1
  • RAID arrays with mdadm: let's say the above disks are joined in a RAID-1 array in /dev/md1
  • volume groups or VG with LVM: the above RAID device (technically a "physical volume" or PV) is assigned into a VG, let's call it vg_tbbuild05 (multiple PVs can be added to a single VG which is why there is that abstraction)
  • LVM logical volumes: out of that volume group actually "virtual partitions" or "logical volumes" are created, that is where your filesystem lives
  • filesystem, typically with ext4: that's your normal filesystem, which treats the logical volume as just another block device
A typical server setup would look like this:
NAME                      MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
nvme0n1                   259:0    0   1.7T  0 disk  
 nvme0n1p1               259:1    0     8M  0 part  
 nvme0n1p2               259:2    0   512M  0 part  
   md0                     9:0    0   511M  0 raid1 /boot
 nvme0n1p3               259:3    0   1.7T  0 part  
   md1                     9:1    0   1.7T  0 raid1 
     crypt_dev_md1       253:0    0   1.7T  0 crypt 
       vg_tbbuild05-root 253:1    0    30G  0 lvm   /
       vg_tbbuild05-swap 253:2    0 125.7G  0 lvm   [SWAP]
       vg_tbbuild05-srv  253:3    0   1.5T  0 lvm   /srv
 nvme0n1p4               259:4    0     1M  0 part
I stripped the other nvme1n1 disk because it's basically the same. Now, if we look at my BTRFS-enabled workstation, which doesn't even have RAID, we have the following:
  • disk: /dev/sda with, again, /dev/sda4 being where BTRFS lives
  • filesystem: fedora_crypt, which is, confusingly, kind of like a volume group. it's where everything lives. i think.
  • subvolumes: home, root, /, etc. those are actually the things that get mounted. you'd think you'd mount a filesystem, but no, you mount a subvolume. that is backwards.
It looks something like this to lsblk:
NAME                   MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                      8:0    0 931,5G  0 disk  
 sda1                   8:1    0   200M  0 part  /boot/efi
 sda2                   8:2    0     1G  0 part  /boot
 sda3                   8:3    0   7,8G  0 part  [SWAP]
 sda4                   8:4    0 922,5G  0 part  
   fedora_crypt       253:4    0 922,5G  0 crypt /srv
Notice how we don't see all the BTRFS volumes here? Maybe it's because I'm mounting this from the Debian side, but lsblk definitely gets confused here. I frankly don't quite understand what's going on, even after repeatedly looking around the rather dismal documentation. But that's what I gather from the following commands:
root@curie:/home/anarcat# btrfs filesystem show
Label: 'fedora'  uuid: 5abb9def-c725-44ef-a45e-d72657803f37
    Total devices 1 FS bytes used 883.29GiB
    devid    1 size 922.47GiB used 916.47GiB path /dev/mapper/fedora_crypt
root@curie:/home/anarcat# btrfs subvolume list /srv
ID 257 gen 108092 top level 5 path home
ID 258 gen 108094 top level 5 path root
ID 263 gen 108020 top level 258 path root/var/lib/machines
I only got to that point through trial and error. Notice how I use an existing mountpoint to list the related subvolumes. If I try to use the filesystem path, the one that's listed in filesystem show, I fail:
root@curie:/home/anarcat# btrfs subvolume list /dev/mapper/fedora_crypt 
ERROR: not a btrfs filesystem: /dev/mapper/fedora_crypt
ERROR: can't access '/dev/mapper/fedora_crypt'
Maybe I just need to use the label? Nope:
root@curie:/home/anarcat# btrfs subvolume list fedora
ERROR: cannot access 'fedora': No such file or directory
ERROR: can't access 'fedora'
This is really confusing. I don't even know if I understand this right, and I've been staring at this all afternoon. Hopefully, the lazyweb will correct me eventually. (As an aside, why are they called "subvolumes"? If something is a "sub" of "something else", that "something else" must exist right? But no, BTRFS doesn't have "volumes", it only has "subvolumes". Go figure. Presumably the filesystem still holds "files" though, at least empirically it doesn't seem like it lost anything so far. In any case, at least I can refer to this section in the future, the next time I fumble around the btrfs commandline, as I surely will. I will possibly even update this section as I get better at it, or based on my reader's judicious feedback.

Mounting BTRFS subvolumes So how did I even get to that point? I have this in my /etc/fstab, on the Debian side of things:
UUID=5abb9def-c725-44ef-a45e-d72657803f37   /srv    btrfs  defaults 0   2
This thankfully ignores all the subvolume nonsense because it relies on the UUID. mount tells me that's actually the "root" (? /?) subvolume:
root@curie:/home/anarcat# mount   grep /srv
/dev/mapper/fedora_crypt on /srv type btrfs (rw,relatime,space_cache,subvolid=5,subvol=/)
Let's see if I can mount the other volumes I have on there. Remember that subvolume list showed I had home, root, and var/lib/machines. Let's try root:
mount -o subvol=root /dev/mapper/fedora_crypt /mnt
Interestingly, root is not the same as /, it's a different subvolume! It seems to be the Fedora root (/, really) filesystem. No idea what is happening here. I also have a home subvolume, let's mount it too, for good measure:
mount -o subvol=home /dev/mapper/fedora_crypt /mnt/home
Note that lsblk doesn't notice those two new mountpoints, and that's normal: it only lists block devices and subvolumes (rather inconveniently, I'd say) do not show up as devices:
root@curie:/home/anarcat# lsblk 
NAME                   MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                      8:0    0 931,5G  0 disk  
 sda1                   8:1    0   200M  0 part  
 sda2                   8:2    0     1G  0 part  
 sda3                   8:3    0   7,8G  0 part  
 sda4                   8:4    0 922,5G  0 part  
   fedora_crypt       253:4    0 922,5G  0 crypt /srv
This is really, really confusing. Maybe I did something wrong in the setup. Maybe it's because I'm mounting it from outside Fedora. Either way, it just doesn't feel right.

No disk usage per volume If you want to see what's taking up space in one of those subvolumes, tough luck:
root@curie:/home/anarcat# df -h  /srv /mnt /mnt/home
Filesystem                Size  Used Avail Use% Mounted on
/dev/mapper/fedora_crypt  923G  886G   31G  97% /srv
/dev/mapper/fedora_crypt  923G  886G   31G  97% /mnt
/dev/mapper/fedora_crypt  923G  886G   31G  97% /mnt/home
(Notice, in passing, that it looks like the same filesystem is mounted in different places. In that sense, you'd expect /srv and /mnt (and /mnt/home?!) to be exactly the same, but no: they are entirely different directory structures, which I will not call "filesystems" here because everyone's head will explode in sparks of confusion.) Yes, disk space is shared (that's the Size and Avail columns, makes sense). But nope, no cookie for you: they all have the same Used columns, so you need to actually walk the entire filesystem to figure out what each disk takes. (For future reference, that's basically:
root@curie:/home/anarcat# time du -schx /mnt/home /mnt /srv
124M    /mnt/home
7.5G    /mnt
875G    /srv
883G    total
real    2m49.080s
user    0m3.664s
sys 0m19.013s
And yes, that was painfully slow.) ZFS actually has some oddities in that regard, but at least it tells me how much disk each volume (and snapshot) takes:
root@tubman:~# time df -t zfs -h
Filesystem         Size  Used Avail Use% Mounted on
rpool/ROOT/debian  3.5T  1.4G  3.5T   1% /
rpool/var/tmp      3.5T  384K  3.5T   1% /var/tmp
rpool/var/spool    3.5T  256K  3.5T   1% /var/spool
rpool/var/log      3.5T  2.0G  3.5T   1% /var/log
rpool/home/root    3.5T  2.2G  3.5T   1% /root
rpool/home         3.5T  256K  3.5T   1% /home
rpool/srv          3.5T   80G  3.5T   3% /srv
rpool/var/cache    3.5T  114M  3.5T   1% /var/cache
bpool/BOOT/debian  571M   90M  481M  16% /boot
real    0m0.003s
user    0m0.002s
sys 0m0.000s
That's 56360 times faster, by the way. But yes, that's not fair: those in the know will know there's a different command to do what df does with BTRFS filesystems, the btrfs filesystem usage command:
root@curie:/home/anarcat# time btrfs filesystem usage /srv
Overall:
    Device size:         922.47GiB
    Device allocated:        916.47GiB
    Device unallocated:        6.00GiB
    Device missing:          0.00B
    Used:            884.97GiB
    Free (estimated):         30.84GiB  (min: 27.84GiB)
    Free (statfs, df):        30.84GiB
    Data ratio:               1.00
    Metadata ratio:           2.00
    Global reserve:      512.00MiB  (used: 0.00B)
    Multiple profiles:              no
Data,single: Size:906.45GiB, Used:881.61GiB (97.26%)
   /dev/mapper/fedora_crypt  906.45GiB
Metadata,DUP: Size:5.00GiB, Used:1.68GiB (33.58%)
   /dev/mapper/fedora_crypt   10.00GiB
System,DUP: Size:8.00MiB, Used:128.00KiB (1.56%)
   /dev/mapper/fedora_crypt   16.00MiB
Unallocated:
   /dev/mapper/fedora_crypt    6.00GiB
real    0m0,004s
user    0m0,000s
sys 0m0,004s
Almost as fast as ZFS's df! Good job. But wait. That doesn't actually tell me usage per subvolume. Notice it's filesystem usage, not subvolume usage, which unhelpfully refuses to exist. That command only shows that one "filesystem" internal statistics that are pretty opaque.. You can also appreciate that it's wasting 6GB of "unallocated" disk space there: I probably did something Very Wrong and should be punished by Hacker News. I also wonder why it has 1.68GB of "metadata" used... At this point, I just really want to throw that thing out of the window and restart from scratch. I don't really feel like learning the BTRFS internals, as they seem oblique and completely bizarre to me. It feels a little like the state of PHP now: it's actually pretty solid, but built upon so many layers of cruft that I still feel it corrupts my brain every time I have to deal with it (needle or haystack first? anyone?)...

Conclusion I find BTRFS utterly confusing and I'm worried about its reliability. I think a lot of work is needed on usability and coherence before I even consider running this anywhere else than a lab, and that's really too bad, because there are really nice features in BTRFS that would greatly help my workflow. (I want to use filesystem snapshots as high-performance, high frequency backups.) So now I'm experimenting with OpenZFS. It's so much simpler, just works, and it's rock solid. After this 8 minute read, I had a good understanding of how ZFS worked. Here's the 30 seconds overview:
  • vdev: a RAID array
  • vpool: a volume group of vdevs
  • datasets: normal filesystems (or block device, if you want to use another filesystem on top of ZFS)
There's also other special volumes like caches and logs that you can (really easily, compared to LVM caching) use to tweak your setup. You might also want to look at recordsize or ashift to tweak the filesystem to fit better your workload (or deal with drives lying about their sector size, I'm looking at you Samsung), but that's it. Running ZFS on Linux currently involves building kernel modules from scratch on every host, which I think is pretty bad. But I was able to setup a ZFS-only server using this excellent documentation without too much problem. I'm hoping some day the copyright issues are resolved and we can at least ship binary packages, but the politics (e.g. convincing Debian that is the right thing to do) and the logistics (e.g. DKMS auto-builders? is that even a thing? how about signed DKMS packages? fun-fun-fun!) seem really impractical. Who knows, maybe hell will freeze over (again) and Oracle will fix the CDDL. I personally think that we should just completely ignore this problem (which wasn't even supposed to be a problem) and ship binary packages directly, but I'm a pragmatic and do not always fit well with the free software fundamentalists. All of this to say that, short term, we don't have a reliable, advanced filesystem/logical disk manager in Linux. And that's really too bad.

8 April 2022

Reproducible Builds: Reproducible Builds in March 2022

Welcome to the March 2022 report from the Reproducible Builds project! In our monthly reports we outline the most important things that we have been up to over the past month.
The in-toto project was accepted as an incubating project within the Cloud Native Computing Foundation (CNCF). in-toto is a framework that protects the software supply chain by collecting and verifying relevant data. It does so by enabling libraries to collect information about software supply chain actions and then allowing software users and/or project managers to publish policies about software supply chain practices that can be verified before deploying or installing software. CNCF foundations hosts a number of critical components of the global technology infrastructure under the auspices of the Linux Foundation. (View full announcement.)
Herv Boutemy posted to our mailing list with an announcement that the Java Reproducible Central has hit the milestone of 500 fully reproduced builds of upstream projects . Indeed, at the time of writing, according to the nightly rebuild results, 530 releases were found to be fully reproducible, with 100% reproducible artifacts.
GitBOM is relatively new project to enable build tools trace every source file that is incorporated into build artifacts. As an experiment and/or proof-of-concept, the GitBOM developers are rebuilding Debian to generate side-channel build metadata for versions of Debian that have already been released. This only works because Debian is (partial) reproducible, so one can be sure that that, if the case where build artifacts are identical, any metadata generated during these instrumented builds applies to the binaries that were built and released in the past. More information on their approach is available in README file in the bomsh repository.
Ludovic Courtes has published an academic paper discussing how the performance requirements of high-performance computing are not (as usually assumed) at odds with reproducible builds. The received wisdom is that vendor-specific libraries and platform-specific CPU extensions have resulted in a culture of local recompilation to ensure the best performance, rendering the property of reproducibility unobtainable or even meaningless. In his paper, Ludovic explains how Guix has:
[ ] implemented what we call package multi-versioning for C/C++ software that lacks function multi-versioning and run-time dispatch [ ]. It is another way to ensure that users do not have to trade reproducibility for performance. (full PDF)

Kit Martin posted to the FOSSA blog a post titled The Three Pillars of Reproducible Builds. Inspired by the shock of infiltrated or intentionally broken NPM packages, supply chain attacks, long-unnoticed backdoors , the post goes on to outline the high-level steps that lead to a reproducible build:
It is one thing to talk about reproducible builds and how they strengthen software supply chain security, but it s quite another to effectively configure a reproducible build. Concrete steps for specific languages are a far larger topic than can be covered in a single blog post, but today we ll be talking about some guiding principles when designing reproducible builds. [ ]
The article was discussed on Hacker News.
Finally, Bernhard M. Wiedemann noticed that the GNU Helloworld project varies depending on whether it is being built during a full moon! (Reddit announcement, openSUSE bug report)

Events There will be an in-person Debian Reunion in Hamburg, Germany later this year, taking place from 23 30 May. Although this is a Debian event, there will be some folks from the broader Reproducible Builds community and, of course, everyone is welcome. Please see the event page on the Debian wiki for more information. Bernhard M. Wiedemann posted to our mailing list about a meetup for Reproducible Builds folks at the openSUSE conference in Nuremberg, Germany. It was also recently announced that DebConf22 will take place this year as an in-person conference in Prizren, Kosovo. The pre-conference meeting (or Debcamp ) will take place from 10 16 July, and the main talks, workshops, etc. will take place from 17 24 July.

Misc news Holger Levsen updated the Reproducible Builds website to improve the documentation for the SOURCE_DATE_EPOCH environment variable, both by expanding parts of the existing text [ ][ ] as well as clarifying meaning by removing text in other places [ ]. In addition, Chris Lamb added a Twitter Card to our website s metadata too [ ][ ][ ]. On our mailing list this month:

Distribution work In Debian this month:
  • Johannes Schauer Marin Rodrigues posted to the debian-devel list mentioning that he exploited the property of reproducibility within Debian to demonstrate that automatically converting a large number of packages to a new internal source version did not change the resulting packages. The proposed change could therefore be applied without causing breakage:
So now we have 364 source packages for which we have a patch and for which we can show that this patch does not change the build output. Do you agree that with those two properties, the advantages of the 3.0 (quilt) format are sufficient such that the change shall be implemented at least for those 364? [ ]
In openSUSE, Bernhard M. Wiedemann posted his usual monthly reproducible builds status report.

Tooling diffoscope is our in-depth and content-aware diff utility. Not only can it locate and diagnose reproducibility issues, it can provide human-readable diffs from many kinds of binary formats. This month, Chris Lamb prepared and uploaded versions 207, 208 and 209 to Debian unstable, as well as made the following changes to the code itself:
  • Update minimum version of Black to prevent test failure on Ubuntu jammy. [ ]
  • Updated the R test fixture for the 4.2.x series of the R programming language. [ ]
Brent Spillner also worked on adding graceful handling for UNIX sockets and named pipes to diffoscope. [ ][ ][ ]. Vagrant Cascadian also updated the diffoscope package in GNU Guix. [ ][ ] reprotest is the Reproducible Build s project end-user tool to build the same source code twice in widely different environments and checking whether the binaries produced by the builds have any differences. This month, Santiago Ruano Rinc n added a new --append-build-command option [ ], which was subsequently uploaded to Debian unstable by Holger Levsen.

Upstream patches The Reproducible Builds project detects, dissects and attempts to fix as many currently-unreproducible packages as possible. We endeavour to send all of our patches upstream where appropriate. This month, we wrote a large number of such patches, including:

Testing framework The Reproducible Builds project runs a significant testing framework at tests.reproducible-builds.org, to check packages and other artifacts for reproducibility. This month, the following changes were made:
  • Holger Levsen:
    • Replace a local copy of the dsa-check-running-kernel script with a packaged version. [ ]
    • Don t hide the status of offline hosts in the Jenkins shell monitor. [ ]
    • Detect undefined service problems in the node health check. [ ]
    • Update the sources.lst file for our mail server as its still running Debian buster. [ ]
    • Add our mail server to our node inventory so it is included in the Jenkins maintenance processes. [ ]
    • Remove the debsecan package everywhere; it got installed accidentally via the Recommends relation. [ ]
    • Document the usage of the osuosl174 host. [ ]
Regular node maintenance was also performed by Holger Levsen [ ], Vagrant Cascadian [ ][ ][ ] and Mattia Rizzolo.
If you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. However, you can get in touch with us via:

19 March 2022

Russell Coker: More About the Librem 5

I concluded my previous post about the Purism Librem 5 [1] with the phone working as a Debian/GNOME system with SSH access over the LAN. Before I published that post I managed to render it unbootable, making a new computer unbootable on the first day of owning it isn t uncommon for me. In this case I tried to get SE Linux running on it and changing the kernel commandline parameter security=apparmor to security=selinux caused it to fail the checksum on kernel parameters and halt the boot. That seems to require a fresh install, it seems possible that I could setup my Librem5 to boot a recovery image from a SD card in such situations but that doesn t seem to be well documented and I didn t have any important data to lose. If I do figure out how to recover data by booting from a micro SD card I ll document it. Here s the documentation for reflashing the phone [2], you have to use the --variant luks option for the flashing tool to have an encrypted root filesystem (should default to on to match the default shipping configuration). There is an option --skip-cleanup to allow you to use the same image multiple times, but that probably isn t useful. The image that is available for download today has the latest kernel update that I installed yesterday so it seems that they quickly update the image which makes it convenient to get the latest (dpkg is slow on low power ARM systems). Overall the flash tool is nicely written, does the download and install and instructs you how to get the phone in flashing mode. It is a minor annoyance that the battery has to be removed as part of the flashing process, I will probably end up flashing my phone more often than I want to take the back off the case. A mitigating factor is that the back is well designed and doesn t appear prone to having it s plastic tabs breaking off when removed (as has happened to several other phones I ve owned). The camera doesn t seem to work well at this time, all photos have an unusually low brightness. The audio recording also doesn t work well, speaking clearly into the phone results in quiet recordings. I updated the Debian Wiki page on Mobile devices [3] to include a link to a page about the Librem5 [4] and to also have a section about applications known to work well on mobile devices. Hopefully other people will make some additions to that as most programs in Debian don t work well on mobile devices so we need a list of known good applications as well as applications that can be easily changed to work well. One thing I ve started looking at is the code for the Geary MUA (the default MUA for the Librem5 and the only one in Debian I know to be suitable for a phone). It needs the Thunderbird style autoconfig and it needs the ability to select which IMAP folders to scan as a common practice is to have some large IMAP folders that aren t used on mobile devices. I believe that Android runs each app in a separate UID to prevent them from messing with each other. The configuration on a standard Linux system and on PureOS is to have all apps running with the same permissions, I think this needs to be improved both for phones and for regular Linux systems which will probably benefit more than phones do. I ll write another blog post about this.

22 February 2022

Russ Allbery: Review: Children of Earth and Sky

Review: Children of Earth and Sky, by Guy Gavriel Kay
Publisher: New American Library
Copyright: 2016
ISBN: 0-698-18327-4
Format: Kindle
Pages: 572
Nine hundred years have passed since the events of Lord of Emperors. Twenty-five years ago, Sarantium, queen of cities, fell to the Osmanlis, who have renamed it Asharias in honor of their Asherite faith. The repercussions are still echoing through the western world, as the Osmanlis attempt each spring to push farther west and the forces of Rodolfo, Holy Emperor in Obravic and defender of the Jaddite faith, hold them back. Seressa and Dubrava are city-state republics built on the sea trade. Seressa is the larger and most renown, money-lenders to Rodolfo and notorious for their focus on business and profit, including willingness to trade with the Osmanlis. Dubrava has a more tenuous position: smaller, reliant on trade and other assistance from Seressa, but also holding a more-favored trading position with Asharias. Both are harassed by piracy from Senjan, a fiercely Jaddite raiding city north up the coast from Dubrava and renown for its bravery against the Asherites. The Senjani are bad for business. Seressa would love to wipe them out, but they have the favor of the Holy Emperor. They settled for attempting to starve the city with a blockade. As Children of Earth and Sky opens, Seressa is sending out new spies. One is a woman named Leonora Valeri, who will present herself as the wife of a doctor that Seressa is sending to Dubrava. She is neither his wife nor Seressani, but this assignment gets her out of the convent to which her noble father exiled her after an unapproved love affair. The other new spy is the young artist Pero Villani, a minor painter whose only notable work was destroyed by the woman who commissioned it for being too revealing. Pero's destination is farther east: Grand Khalif Gur u the Destroyer, the man whose forces took Sarantium, wants to be painted in the western style. Pero will do so, and observe all he can, and if the opportunity arises to do more than that, well, so much the better. Pero and Leonora are traveling on a ship owned by Marin Djivo, the younger son of a wealthy Dubravan merchant family, when their ship is captured by Senjani raiders. Among the raiders is Danica Gradek, the archer who broke the Seressani blockade of Senjan. This sort of piracy, while tense, should be an economic transaction: some theft, some bargaining, some ransom, and everyone goes on their way. That is not what happens. Moments later, two men lie dead, and Danica's life has become entangled with Dubravan merchants and Seressani spies. Children of Earth and Sky is in some sense a sequel to the Sarantine Mosaic, and knowing the events of that series adds some emotional depth and significant moments to this story, but you can easily read it as a stand-alone novel. (That said, I recommend the Sarantine Mosaic regardless.) As with nearly all of Kay's work, it's historical fiction with the names changed (less this time than in most of this books) and a bit of magic added. The setting is the middle of the 15th century. Seressa is, of course, Venice. The Osmanlis are the Ottoman Turks, and Asharias is Istanbul, the captured Constantinople. Rodolfo is a Habsburg Holy Roman Emperor, holding court in an amalgam of northern cities that (per the afterward) is primarily Prague. Dubrava, which is central to much of this book, is Dubrovnik in Croatia. As usual with Kay's novels, you don't need to know this to enjoy the story, but it may spark some fun secondary reading. The touch of magic is present in several places, but comes primarily from Danica, whose grandfather resides as a voice in her head. He is the last of her family that she is in contact with. Her father and older brother were killed by Osmanli raiders, and her younger brother taken as a slave to be raised as a djanni warrior in the khalif's infantry. (Djannis are akin to Mamluks in our world.) Damaz, as he is now known, is the remaining major viewpoint character I've not mentioned. There are a couple of key events in the book that have magic at the center, generally involving Danica or Damaz, but most of the story is straight historical fiction (albeit with significant divergences from our world). I'd talked myself out of starting this novel several times before I finally picked it up. Like most of Kay's, it's a long book, and I wasn't sure if I was in the mood for epic narration and a huge cast. And indeed, I found it slow at the start. Once the story got underway, though, I was as enthralled as always. There is a bit of sag in the middle of the book, in part because Kay didn't follow up on some relationships that I wish were more central to the plot and in part because he overdoes the narrative weight in one scene, but the ending is exceptional. Guy Gavriel Kay is the master of a specific type of omniscient tight third person narration, one in which the reader sees what a character is thinking but also gets narrative commentary, foreshadowing, and emotional emphasis apart from the character's thoughts. It can feel heavy-handed; if something is important, Kay tells you, explicitly and sometimes repetitively, and the foreshadowing frequently can be described as portentous. But in return, Kay gets fine control of pacing and emphasis. The narrative commentary functions like a soundtrack in a movie. It tells you when to pay close attention and when you can relax, what moments are important, where to slow down, when to brace yourself, and when you can speed up. That in turn requires trust; if you're not in the mood for the author to dictate your reading pace to the degree Kay is attempting, it can be irritating. If you are in the mood, though, it makes his novels easy to relax into. The narrator will ensure that you don't miss anything important, and it's an effective way to build tension. Kay also strikes just the right balance between showing multiple perspectives on a single moment and spending too much time retelling the same story. He will often switch viewpoint characters in the middle of a scene, but he avoids the trap of replaying the scene and thus losing the reader's interest. There is instead just a moment of doubled perspective or retrospective commentary, just enough information for the reader to extrapolate the other character's experience backwards, and then the story moves on. Kay has an excellent feel for when I badly wanted to see another character's perspective on something that just happened. Some of Kay's novels revolve around a specific event or person. Children of Earth and Sky is not one of those. It's a braided novel following five main characters, each with their own story. Some of those stories converge; some of them touch for a while and then diverge again. About three-quarters of the way through, I wasn't sure how Kay would manage a satisfying conclusion for the numerous separate threads that didn't feel rushed, but I need not have worried. The ending had very little of the shape that I had expected, focused more on the small than the large (although there are some world-changing events here), but it was an absolute delight, with some beautiful moments of happiness that took the rest of the novel to set up. This is not the sort of novel with a clear theme, but insofar as it has one, it's a story about how much of the future shape and events of the world are unknowable. All we can control is our own choices, and we may never know their impact. Each individual must decide who they want to be and attempt to live their life in accordance with that decision, hopefully with some grace towards others in the world. The novel does, alas, still have some of Kay's standard weaknesses. There is (at last!) an important female friendship, and I had great hopes for a second one, but sadly it lasted only a scant handful of pages. Men interact with each other and with women; women interact almost exclusively with men. Kay does slightly less awarding of women to male characters than in some previous books (although it still happens), but this world is still weirdly obsessed with handing women to men for sex as a hospitality gesture. None of this is too belabored or central to the story, or I would be complaining more, but as soon as one sees how regressive the gender roles typically are in a Kay novel, it's hard to unsee. And, as always for Kay, the sex in this book is weirdly off-putting to me. I think this goes hand in hand with Kay's ability to write some of the best conversations in fantasy. Kay's characters spar and thrust with every line and read nuance into small details of wording. Frequently, the turn of the story rests on the outcome of a careful conversation. This is great reading; it's the part of Kay's writing I enjoy the most. But I'm not sure he knows how to turn it off between characters who love and trust each other. The characters never fully relax; sex feels like another move in ongoing chess games, which in turn makes it feel weirdly transactional or manipulative instead of open-hearted and intimate. It doesn't help that Kay appears to believe that arousal is a far more irresistible force for men than I do. Those problems did get in the way of my enjoyment occasionally, but I didn't think they ruined the book. The rest of the story is too good. Danica in particular is a wonderful character: thoughtful, brave, determined, and deeply honest with herself in that way that is typical of the best of Kay's characters. I wanted to read the book where Danica's and Leonora's stories stayed more entwined; alas, that's not the story Kay was writing. But I am in awe at Kay's ability to write characters who feel thoughtful and insightful even when working at cross purposes, in a world that mostly avoids simple villains, with a plot that never hinges on someone doing something stupid. I love reading about these people. Their triumphs, when they finally come, are deeply satisfying. Children of Earth and Sky is probably not in the top echelon of Kay's works with the Sarantine Mosaic and Under Heaven, but it's close. If you like his other writing, you will like this as well. Highly recommended. Rating: 9 out of 10

26 January 2022

Timo Jyrinki: Unboxing Dell XPS 13 - openSUSE Tumbleweed alongside preinstalled Ubuntu

A look at the 2021 model of Dell XPS 13 - available with Linux pre-installed
I received a new laptop for work - a Dell XPS 13. Dell has been long famous for offering certain models with pre-installed Linux as a supported option, and opting for those is nice for moving some euros/dollars from certain PC desktop OS monopoly towards Linux desktop engineering costs. Notably Lenovo also offers Ubuntu and Fedora options on many models these days (like Carbon X1 and P15 Gen 2).
black box

opened box

accessories and a leaflet about Linux support

laptop lifted from the box, closed

laptop with lid open

Ubuntu running

openSUSE runnin
Obviously a smooth, ready-to-rock Ubuntu installation is nice for most people already, but I need openSUSE, so after checking everything is fine with Ubuntu, I continued to install openSUSE Tumbleweed as a dual boot option. As I m a funny little tinkerer, I obviously went with some special things. I wanted:
  • Ubuntu to remain as the reference supported OS on a small(ish) partition, useful to compare to if trying out new development versions of software on openSUSE and finding oddities.
  • openSUSE as the OS consuming most of the space.
  • LUKS encryption for openSUSE without LVM.
  • ext4 s new fancy fast_commit feature in use during filesystem creation.
  • As a result of all that, I ended up juggling back and forth installation screens a couple of times (even more than shown below, and also because I forgot I wanted to use encryption the first time around).
First boots to pre-installed Ubuntu and installation of openSUSE Tumbleweed as the dual-boot option:
(if the embedded video is not shown, use a direct link)
Some notes from the openSUSE installation:
  • openSUSE installer s partition editor apparently does not support resizing or automatically installing side-by-side another Linux distribution, so I did part of the setup completely on my own.
  • Installation package download hanged a couple of times, only passed when I entered a mirror manually. On my TW I ve also noticed download problems recently, there might be a problem with some mirror I need to escalate.
  • The installer doesn t very clearly show encryption status of the target installation - it took me a couple of attempts before I even noticed the small encrypted column and icon (well, very small, see below), which also did not spell out the device mapper name but only the main partition name. In the end it was going to do the right thing right away and use my pre-created encrypted target partition as I wanted, but it could be a better UX. Then again I was doing my very own tweaks anyway.
  • Let s not go to the details why I m so old-fashioned and use ext4 :)
  • openSUSE s installer does not work fine with HiDPI screen. Funnily the tty consoles seem to be fine and with a big font.
  • At the end of the video I install the two GNOME extensions I can t live without, Dash to Dock and Sound Input & Output Device Chooser.

13 January 2022

Bits from Debian: New Debian Developers and Maintainers (November and December 2021)

The following contributors got their Debian Developer accounts in the last two months: The following contributors were added as Debian Maintainers in the last two months: Congratulations!

29 December 2021

Chris Lamb: Favourite books of 2021: Memoir/biography

Just as I did for 2020, I won't publically disclose exactly how many books I read in 2021, but they evidently provoked enough thoughts that felt it worth splitting my yearly writeup into separate posts. I will reveal, however, that I got through more books than the previous year, and, like before, I enjoyed the books I read this year even more in comparison as well. How much of this is due to refining my own preferences over time, and how much can be ascribed to feeling less pressure to read particular books? It s impossible to say, and the question is complicated further by the fact I found many of the classics I read well worth of their entry into the dreaded canon. But enough of the throat-clearing. In today's post I'll be looking at my favourite books filed under memoir and biography, in no particular order. Books that just missed the cut here include: Bernard Crick's celebrated 1980 biography of George Orwell, if nothing else because it was a pleasure to read; Hilary Mantel's exhilaratingly bitter early memoir, Giving up the Ghost (2003); and Patricia Lockwood's hilarious Priestdaddy (2017). I also had a soft spot for Tim Kreider's We Learn Nothing (2012) as well, despite not knowing anything about the author in advance, likely a sign of good writing. The strangest book in this category I read was definitely Michelle Zauner's Crying in H Mart. Based on a highly-recommended 2018 essay in the New Yorker, its rich broth of genuine yearning for a departed mother made my eyebrows raise numerous times when I encountered inadvertent extra details about Zauner's relationships.

Beethoven: A Life in Nine Pieces (2020) Laura Tunbridge Whilst it might immediately present itself as a clickbait conceit, organising an overarching narrative around just nine compositions by Beethoven turns out to be an elegant way of saying something fresh about this grizzled old bear. Some of Beethoven's most famous compositions are naturally included in the nine (eg. the Eroica and the Hammerklavier piano sonata), but the book raises itself above conventional Beethoven fare when it highlights, for instance, his Septet, Op. 20, an early work that is virtually nobody's favourite Beethoven piece today. The insight here is that it was widely popular in its time, played again and again around Vienna for the rest of his life. No doubt many contemporary authors can relate to this inability to escape being artistically haunted by an earlier runaway success. The easiest way to say something interesting about Beethoven in the twenty-first century is to talk about the myth of Beethoven instead. Or, as Tunbridge implies, perhaps that should really be 'Beethoven' in leaden quotation marks, given so much about what we think we know about the man is a quasi-fictional construction. Take Anton Schindler, Beethoven's first biographer and occasional amanuensis, who destroyed and fabricated details about Beethoven's life, casting himself in a favourable light and exaggerating his influence with the composer. Only a few decades later, the idea of a 'heroic' German was to be politically useful as well; the Anglosphere often need reminding that Germany did not exist as a nation-state prior to 1871, so it should be unsurprising to us that the late nineteenth-century saw a determined attempt to create a uniquely 'German' culture ex nihilo. (And the less we say about Immortal Beloved the better, even though I treasure that film.) Nevertheless, Tunbridge cuts through Beethoven's substantial legacy using surgical precision that not only avoids feeling like it is settling a score, but it also does so in a way that is unlikely to completely alienate anyone emotionally dedicated to some already-established idea of the man to bring forth the tediously predictable sentiment that Beethoven has 'gone woke'. With Alex Ross on the cult of Wagner, it seems that books about the 'myth of X' are somewhat in vogue right now. And this pattern within classical music might fit into some broader trend of deconstruction in popular non-fiction too, especially when we consider the numerous contemporary books on the long hangover of the Civil Rights era (Robin DiAngelo's White Fragility, etc.), the multifarious ghosts of Empire (Akala's Natives, Sathnam Sanghera's Empireland, etc.) or even the 'transmogrification' of George Orwell into myth. But regardless of its place in some wider canon, A Life in Nine Pieces is beautifully printed in hardback form (worth acquiring for that very reason alone), and it is one of the rare good books about classical music that can be recommended to both the connoisseur and the layperson alike.

Sea State (2021) Tabitha Lasley In her mid-30s and jerking herself out of a terrible relationship, Tabitha Lasley left London and put all her savings into a six-month lease on a flat within a questionable neighbourhood in Aberdeen, Scotland. She left to make good on a lukewarm idea for a book about oil rigs and the kinds of men who work on them: I wanted to see what men were like with no women around, she claims. The result is Sea State, a forthright examination of the life of North Sea oil riggers, and an unsparing portrayal of loneliness, masculinity, female desire and the decline of industry in Britain. (It might almost be said that Sea State is an update of a sort to George Orwell's visit to the mines in the North of England.) As bracing as the North Sea air, Sea State spoke to me on multiple levels but I found it additionally interesting to compare and contrast with Julian Barnes' The Man with Red Coat (see below). Women writers are rarely thought to be using fiction for higher purposes: it is assumed that, unlike men, whatever women commit to paper is confessional without any hint of artfulness. Indeed, it seems to me that the reaction against the decades-old genre of autofiction only really took hold when it became the domain of millennial women. (By contrast, as a 75-year-old male writer with a firmly established reputation in the literary establishment, Julian Barnes is allowed wide latitude in what he does with his sources and his writing can be imbued with supremely confident airs as a result.) Furthermore, women are rarely allowed metaphor or exaggeration for dramatic effect, and they certainly aren t permitted to emphasise darker parts in order to explore them... hence some of the transgressive gratification of reading Sea State. Sea State is admittedly not a work of autofiction, but the sense that you are reading about an author writing a book is pleasantly unavoidable throughout. It frequently returns to the topic of oil workers who live multiple lives, and Lasley admits to living two lives herself: she may be in love but she's also on assignment, and a lot of the pleasure in this candid and remarkably accessible book lies in the way these states become slowly inseparable.

Twilight of Democracy (2020) Anne Applebaum For the uninitiated, Anne Applebaum is a staff writer for The Atlantic magazine who won a Pulitzer-prize for her 2004 book on the Soviet Gulag system. Her latest book, however, Twilight of Democracy is part memoir and part political analysis and discusses the democratic decline and the rise of right-wing populism. This, according to Applebaum, displays distinctly authoritarian tendencies, and who am I to disagree? Applebaum does this through three main case studies (Poland, the United Kingdom and the United States), but the book also touches on Hungary as well. The strongest feature of this engaging book is that Appelbaum's analysis focuses on the intellectual classes and how they provide significant justification for a descent into authoritarianism. This is always an important point to be remembered, especially as much of the folk understanding of the rise of authoritarian regimes tends to place exaggerated responsibility on the ordinary and everyday citizen: the blame placed on the working-class in the Weimar Republic or the scorn heaped upon 'white trash' of the contemporary Rust Belt, for example. Applebaum is uniquely poised to discuss these intellectuals because, well, she actually knows a lot of them personally. Or at least, she used to know them. Indeed, the narrative of the book revolves around two parties she hosted, both in the same house in northwest Poland. The first party, on 31 December 1999, was attended by friends from around the Western world, but most of the guests were Poles from the broad anti-communist alliance. They all agreed about democracy, the rule of law and the route to prosperity whilst toasting in the new millennium. (I found it amusing to realise that War and Peace also starts with a party.) But nearly two decades later, many of the attendees have ended up as supporters of the problematic 'Law and Justice' party which currently governs the country. Applebaum would now cross the road to avoid them, and they would do the same to her, let alone behave themselves at a cordial reception. The result of this autobiographical detail is that by personalising the argument, Applebaum avoids the trap of making too much of high-minded abstract argument for 'democracy', and additionally makes her book compellingly spicy too. Yet the strongest part of this book is also its weakest. By individualising the argument, it often feels that Applebaum is settling a number of personal scores. She might be very well justified in doing this, but at times it feels like the reader has walked in halfway through some personal argument and is being asked to judge who is in the right. Furthermore, Applebaum's account of contemporary British politics sometimes deviates into the cartoonish: nothing was egregiously incorrect in any of her summations, but her explanation of the Brexit referendum result didn't read as completely sound. Nevertheless, this lively and entertaining book that can be read with profit, even if you disagree with significant portions of it, and its highly-personal approach makes it a refreshing change from similar contemporary political analysis (eg. David Runciman's How Democracy Ends) which reaches for that more 'objective' line.

The Man in the Red Coat (2019) Julian Barnes As rich as the eponymous red coat that adorns his cover, Julian Barnes quasi-biography of French gynaecologist Samuel-Jean Pozzi (1846 1918) is at once illuminating, perplexing and downright hilarious. Yet even that short description is rather misleading, for this book evades classification all manner number of ways. For instance, it is unclear that, with the biographer's narrative voice so obviously manifest, it is even a biography in the useful sense of the word. After all, doesn't the implied pact between author and reader require the biographer to at least pretend that they are hiding from the reader? Perhaps this is just what happens when an author of very fine fiction turns his hand to non-fiction history, and, if so, it represents a deeper incursion into enemy territory after his 1984 metafictional Flaubert's Parrot. Indeed, upon encountering an intriguing mystery in Pozzi's life crying out for a solution, Barnes baldly turns to the reader, winks and states: These matters could, of course, be solved in a novel. Well, quite. Perhaps Barnes' broader point is that, given that's impossible for the author to completely melt into air, why not simply put down your cards and have a bit of fun whilst you're at it? If there's any biography that makes the case for a rambling and lightly polemical treatment, then it is this one. Speaking of having fun, however, two qualities you do not expect in a typical biography is simply how witty they can be, as well as it having something of the whiff of the thriller about it. A bullet might be mentioned in an early chapter, but given the name and history of Monsieur Pozzi is not widely known, one is unlikely to learn how he lived his final years until the closing chapters. (Or what happened to that turtle.) Humour is primarily incorporated into the book in two main ways: first, by explicitly citing the various wits of the day ( What is a vice? Merely a taste you don t share. etc.), but perhaps more powerful is the gentle ironies, bon mots and observations in Barnes' entirely unflappable prose style, along with the satire implicit in him writing this moreish pseudo-biography to begin with. The opening page, with its steadfast refusal to even choose where to begin, is somewhat characteristic of Barnes' method, so if you don't enjoy the first few pages then you are unlikely to like the rest. (Indeed, the whole enterprise may be something of an acquired taste. Like Campari.) For me, though, I was left wryly grinning and often couldn't wait to turn the page. Indeed, at times it reminded me of a being at a dinner party with an extremely charming guest at the very peak of his form as a wit and raconteur, delighting the party with his rambling yet well-informed discursive on his topic de jour. A significant book, and a book of significance.

12 November 2021

Jonathan Dowland: Frictionless external backups with systemd

Here's a description of how my monthly external backups are managed at a technical level. I didn't realise I hadn't written this all down anywhere yet. What
blinkenlights! blinkenlights!
I plug in one of two (prepared) external hard drives into my headless NAS. The NAS contains my primary data backup. A job automatically decrypts the encrypted filesystem on the drive, mounts it and synchronises the copy of my backup data on the drive from that on the NAS. Whilst this is going on, the blinkstick LED on the NAS switches to a colour to signal "in progress". When it's done, the light changes to green to signal "done" and I can remove it. If something goes wrong, it turns red and I get mail. Why I want a third-strand, off-site backup of my and my family's data in case of a disaster in our house. For it to be useful it has to be regular, so I needed to remove as much of the friction of performing the backup as possible. I use two drives alternately so that I don't have all my eggs in one basket in the window when I bring one of them home and perform the backup. How As much as possible I lean on systemd and its ability to trigger actions based on events.
  1. External drive is plugged in. systemd instantiates a corresponding device unit, named dev-disk-by\x2duuid-aaaaaaaa\x2daaaa\x2daaaa\x2daaaa\x2daaaaaaaaaaaa.device, where aaaa is the UUID of a partition on the device
  2. The backup job is a systemd service which has a WantedBy relationship on the device unit, so when the device appears, systemd starts the backup service.
  3. The backup service has Requires and After relationships on systemd-cryptsetup@extbackup.service, a service created by systemd's cryptsetup generator on start-up (but slightly customised, see below). The encrypted device is therefore unlocked.
  4. The backup service defines multiple start and stop commands with ExecStart and ExecStop. These are used to:
    1. set the blinkstick to the working colour (blue-ish)
    2. mount the now-decrypted filesystem
    3. get a lock on the backup repository (so nothing else writes to it) and synchronise the files
    4. unmount the filesystem
    5. set the blinkstick to the success colour (green)
  5. Finally, the systemd-cryptsetup@extbackup.service unit realises it is not required any more. It has been customised with StopWhenUnneeded=true1, so the encrypted filesystem is closed, ready for the drive to be removed.
  6. I notice the LED colour is green, remove the drive, and take it to its off-site home.
If anything goes wrong, all my custom systemd units have, as a matter of course,
OnFailure=status-email-user@%n.service blinkstick-fail.service
Preparing a new backup disk This is mostly just a standard dm-crypt/cryptsetup/LUKS encrypted device, on top of a standard partition on the underlying disk, with a normal filesystem sitting on top: Basically, the most common way to encrypt a drive in Linux. See places like the cryptsetup docs for how to set something like that up. The key things here are The backup service Here's the backup service unit definition in its entirety:
 [Unit]
 OnFailure=status-email-user@%n.service blinkstick-fail.service
 Requires=systemd-cryptsetup@extbackup.service backup.mount
 After=systemd-cryptsetup@extbackup.service backup.mount
 [Service]
 Type=oneshot
 ExecStart=/usr/local/bin/blinkstick --index 1 --limit 10 --set-color 33c280
 ExecStart=/bin/mount /extbackup
 ExecStart=/home/jon/bin/phobos-backup-monthly
 ExecStop=/bin/umount /extbackup
 ExecStop=/usr/local/bin/blinkstick --index 1 --limit 10 --set-color green
 [Install]
 WantedBy=dev-disk-by\x2duuid-aaaaaaaa\x2daaaa\x2daaaa\x2daaaa\x2daaaaaaaaaaaa.device
The dashes in the UUID in WantedBy= need to be encoded as \x2d and then the slashes from the path bit as dashes. Using dashes to encode slashes is possibly the single most frustrating systemd design decision. Issues Sadly (as detailed in Blinkenlights, part 2) there are 2 some frustrating limitations with trying to handle the mount (and unmount) of the filesystem in systemd-land, so instead, it's done using the traditional mount, umount and fstab. If you can point out any improvements to this approach, please let me know!

  1. I customized mine a while ago by copying the generated service file to a static file, but nowadays I think you could do systemd edit systemd-cryptsetup@extbackup.service to add the StopWhenUnneeded to an override file and not need the rest.
  2. or at least were. It's been a while since I revisited this part.

31 October 2021

Russ Allbery: Review: Shadow Scale

Review: Shadow Scale, by Rachel Hartman
Series: Seraphina #2
Publisher: Ember
Copyright: 2015
ISBN: 0-375-89659-7
Format: Kindle
Pages: 458
Shadow Scale, despite confusing publisher marketing that calls it a "companion" to Seraphina, is a direct sequel. It picks up shortly after Seraphina and resolves most of the loose ends of the previous book. This is a book for which my completionist tendencies did me no favors. The book I was intending to read, when I started on Hartman's work, is Tess of the Road, but I hate starting series in the middle and it was clear that Tess was set after Seraphina. (I have been repeatedly assured that this doesn't matter and that one can start with Tess. Such reassurances rarely work on me; do as I say, not as I do.) For Seraphina itself, this turned out fine; I'm mildly surprised by the book's Andre Norton award nomination, but it was enjoyable enough and I liked the first-person protagonist. Shadow Scale I approached with a bit more trepidation. I hadn't heard much about it and the few reviews I saw were lukewarm. Unfortunately, there's a reason for that. Seraphina left obvious room for a sequel, including a brewing war, significant unresolved interpersonal relationships, and Seraphina's own newfound understanding of the nature of her internal menagerie. Alas, the start of the book uses the war primarily as plot device (and introduces a brand-new bit of magic that I never found interesting), largely ignores the relationship, and focuses on that third plot element. And by focuses, I mean Seraphina is sent out of the country of Goredd on a journey of map exploration to collect plot coupons. The best description I have for the middle of this book is tedious and depressing. Like a lot of novels, it has a U-shaped plot: things get worse and worse until a crisis, and then start getting better. This plot can work, but the reader has to have a good reason to stick through the depressing bits. One of the better reasons is if the plot allows the main character some small triumphs, maintaining their agency throughout even if larger events are spiraling out of control. This is not one of those books. After some early successes tracking down some objects of her search, Seraphina encounters an antagonist from her own past (barely hinted at in the first book) who can systematically corrupt everything she is trying to do. She spends most of the book feeling like what she's doing is futile, or hoping for things the reader knows aren't going to happen. Given that this is happening during plodding map exploration fantasy through largely indistinguishable faux-medieval countries, or (later) somewhat more interesting but obviously irrelevant local politics in a remote trading city, it's hard to avoid sharing that sense of futility. The other structural problem with Shadow Scale is that the plot coupons are people, which means this book has an excessive cast size problem. Seraphina collects too many people for me to even keep straight, let alone care about. Critical developments (usually for the worst) in the lives of one of these characters were frequently met with reader mutterings like, "Now which one was Brasidas again, was he the plague doctor?" This tends to undermine the emotional impact. It didn't help that the plot was enough of a slog that I kept putting the book aside for a few days. This does get better, but not enough better to redeem the middle of the book, and one has to put up with a lot of helpless despair to get there. Shadow Scale is one of those stories where the protagonist has the innate power to resolve the plot, is told cryptically by various people that this is the case, but has absolutely no idea how to use it and her supposed mentors are essentially useless. The result is that she feels both hopeless and guilty, which was not the reading experience I wanted. I did enjoy the moment when she finally figures it out, and I thought Hartman's idea was reasonably clever, but it would have been better if that had happened faster. Like, 200 pages faster. At least. The major world-building in Seraphina was the dragons. The dragons also show up in this book (and feel less like autism spectrum archetypes, which I appreciated), and in theory are central to the plot, but I'm not entirely sure why? It was an odd reading experience. I think Hartman was attempting to set up dual villains posing different threats, but the dragon one is off-screen for nearly the entire book and never developed, so it feels perfunctory. Near the end of the book, Hartman abruptly picks up the dragons again, but that whole section felt oddly disconnected from the rest of the plot and is only barely relevant to the resolution. At least for me, the plot structure didn't cohere. Shadow Scale does go up a whole point in rating for me because of the romance plot and how Hartman resolves it, which I will not spoil but which I loved. The process of getting there is immensely frustrating because it feels like Hartman is forcing the characters into a corner where only stupid resolutions are possible, but in this case the U-shaped emotional structure worked on me. The ending is completely true to the characters in a way that I thought Hartman had made impossible (and which does a lovely bit of undermining of traditional roles), so full credit there. It helped that the relationship is put on ice for most of the book and only appears at the end (which is also the best part of the book), so it didn't drag on like the other parts of the plot. Overall, though, I tentatively agree with the general advice to skip this one, and suspect that advice will become less tentative once I read Tess of the Road. It's a largely unpleasant slog. There are some mildly interesting world-building revelations that fill in the background of Seraphina, the ending was reasonably good, and the relationships were much better than I was expecting through most of the book, but the amount of time and patience required to get there was not a good trade-off for me. Followed (in the sense that it's set in the same universe but is not a sequel and I suspect does not depend heavily on this plot) by Tess of the Road. Rating: 4 out of 10

7 July 2021

Dirk Eddelbuettel: Rcpp 1.0.7: More Updates

rcpp logo The Rcpp team is pleased to announce release 1.0.7 of Rcpp which arrived at CRAN earlier today, and will be uploaded to Debian shortly. Windows and macOS builds should appear at CRAN in the next few days. This release continues with the six-months cycle started with release 1.0.5 last July. As a reminder, interim dev or rc releases will alwasys be available in the Rcpp drat repo; this cycle there were seven (!!). These rolling release tend to work just as well, and are also fully tested against all reverse-dependencies. Rcpp has become the most popular way of enhancing R with C or C++ code. As of today, 2323 packages on CRAN depend on Rcpp for making analytical code go faster and further, along with 227 in BioConductor. This release contains a change which Luke Tierney urged us to make a good year ago in #1081) (and which we had looked at earlier in #382). Implementing the change in a regular update proved a little tricky, and my initial branch lay dormant until I aki revived it, and finished the transition (which we then did in two PRs). The change concerns how Rcpp grows internal objects, and the new approach (thanks to the hint by Luke) closer to what R does guaranteeing linear behaviour. It turns out that we overlooked one aspect (of coping with Modules built under earlier Rcpp releases) so the initial upload to CRAN on Saturday revealed that we needed a small adjustment that we made for the final release. This version should now be more performant, and rest on a stable API. Based on the reverse depends checks by both us and CRAN (using the updated version), we expect no issues with existing code. However, it something does act up a fresh compilation of the packages using Rcpp may help. We also made a few other minor changes in the API such as silencing a silly compiler warning, ensuring global Rcout and Rcerr objects, adding support for a new Rcpp::message() call, completing a switch to uint32_t instead of unsigned int and including the cfloat header (which relates to STRICT_R_HEADERS discussed below). Similarly, the Rcpp Attributes feature was enhanced by coping better with packages with a dot in their name and their for per-package include files, along with support for more quiet compilation if desired. As some Rcpp users may have seen, we plan to enable STRICT_R_HEADERS by the next release (expected in January 2022). A long issue tick #1158 is laying the ground work. Maintainers of 81 packages which are affected and need a small change (such as for example switching from PI to M_PI); of these 56 have already responded. We plan to be in touch in the fall. Adding the cfloat header is one help in this transition (as the corresponding C header was pulled in when STRICT_R_HEADERS is not defined) as it ensures DBL_EPSILON and alike are defined. Last but not least this is also the first relase in which we welcome I aki as a new member of the Rcpp Core team. Yay! The NEWS file entries follow summarizing the nine key PRs in this release.

Changes in Rcpp release version 1.0.7 (2021-07-06)
  • Changes in Rcpp API:
    • Refactored Rcpp_PreserveObject and Rcpp_ReleaseObject which are now O(1) (Dirk and I aki in #1133 and #1135 fixing #382 and #1081).
    • A spuriously assigned variable was removed (Dirk in #1138 fixing #1137).
    • Global Rcout and Rcerr objects are supported via a compiler directive (I aki in #1139 fixing #928)
    • Add support for Rcpp::message (Dirk in #1146 fixing #1145).
    • The uint32_t type is used throughout instead of unsigned int (Dirk in #1153 fixing #1152).
    • The cfloat header for floating point limits is now included (Dirk in #1162 fixing #1161).
  • Changes in Rcpp Attributes:
    • Packages with dots in their name can now have per-package include files (Dirk in #1132 fixing #1129).
    • New argument echo to quieten optional evaluation in sourceCpp (Dirk in #1138 fixing #1126).
  • Forthcoming Changes in Rcpp API:
    • Starting with Rcpp 1.0.8 anticipated in January 2022, STRICT_R_HEADERS will be enabled by default, see #1126.

Thanks to my CRANberries, you can also look at a diff to the previous release. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page. Bugs reports are welcome at the GitHub issue tracker as well (where one can also search among open or closed issues); questions are also welcome under rcpp tag at StackOverflow which also allows searching among the (currently) 2616 previous questions. If you like this or other open-source work I do, you can sponsor me at GitHub.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

29 May 2021

Joey Hess: the end of the olduse.net exhibit

Ten years ago I began the olduse.net exhibit, spooling out Usenet history in real time with a 30 year delay. My archive has reached its end, and ten years is more than long enough to keep running something you cobbled together overnight way back when. So, this is the end for olduse.net. The site will continue running for another week or so, to give you time to read the last posts. Find the very last one, if you can! The source code used to run it, and the content of the website have themselves been archived up for posterity at The Internet Archive. Sometime in 2022, a spammer will purchase the domain, but not find it to be of much value. The Utzoo archives that underlay it have currently sadly been censored off the Internet by someone. This will be unsuccessful; by now they have spread and many copies will live on.
I told a lie ten years ago.
You can post to olduse.net, but it won't show up for at least 30 years.
Actually, those posts drop right now! Here are the followups to 30-year-old Usenet posts that I've accumulated over the past decade. Mike replied in 2011 to JPM's post in 1981 on fa.arms-d "Re: CBS Reports"
A greeting from the future: I actually watched this yesterday (2011-06-10) after reading about it here.
Christian Brandt replied in 2011 to schrieb phyllis's post in 1981 on the "comments" newsgroup "Re: thank you rrg"
Funny, it will be four years until you post the first subnet post i ever read and another eight years until my own first subnet post shows up.
Bernard Peek replied in 2012 to mark's post in 1982 on net.sf-lovers "Re: luke - vader relationship"
i suggest that darth vader is luke skywalker's mother.
You may be on to something there.
Martijn Dekker replied in 2012 to henry's post in 1982 on the "test" newsgroup "Re: another boring test message" trentbuck replied in 2012 to dwl's post in 1982 on the "net.jokes" newsgroup "Re: A child hood poem" Eveline replied in 2013 to a post in 1983 on net.jokes.q "Re: A couple"
Ha!
Bill Leary replied in 2015 to Darin Johnson's post in 1985 on net.games.frp "Re: frp & artwork" Frederick Smith replied in 2021 to David Hoopes's post in 1990 on trial.rec.metalworking "Re: Is this group still active?"

11 April 2021

Vishal Gupta: Sikkim 101 for Backpackers

Host to Kanchenjunga, the world s third-highest mountain peak and the endangered Red Panda, Sikkim is a state in northeastern India. Nestled between Nepal, Tibet (China), Bhutan and West Bengal (India), the state offers a smorgasbord of cultures and cuisines. That said, it s hardly surprising that the old spice route meanders through western Sikkim, connecting Lhasa with the ports of Bengal. Although the latter could also be attributed to cardamom (kali elaichi), a perennial herb native to Sikkim, which the state is the second-largest producer of, globally. Lastly, having been to and lived in India, all my life, I can confidently say Sikkim is one of the cleanest & safest regions in India, making it ideal for first-time backpackers.

Brief History
  • 17th century: The Kingdom of Sikkim is founded by the Namgyal dynasty and ruled by Buddhist priest-kings known as the Chogyal.
  • 1890: Sikkim becomes a princely state of British India.
  • 1947: Sikkim continues its protectorate status with the Union of India, post-Indian-independence.
  • 1973: Anti-royalist riots take place in front of the Chogyal's palace, by Nepalis seeking greater representation.
  • 1975: Referendum leads to the deposition of the monarchy and Sikkim joins India as its 22nd state.
Languages
  • Official: English, Nepali, Sikkimese/Bhotia and Lepcha
  • Though Hindi and Nepali share the same script (Devanagari), they are not mutually intelligible. Yet, most people in Sikkim can understand and speak Hindi.
Ethnicity
  • Nepalis: Migrated in large numbers (from Nepal) and soon became the dominant community
  • Bhutias: People of Tibetan origin. Major inhabitants in Northern Sikkim.
  • Lepchas: Original inhabitants of Sikkim

Food
  • Tibetan/Nepali dishes (mostly consumed during winter)
    • Thukpa: Noodle soup, rich in spices and vegetables. Usually contains some form of meat. Common variations: Thenthuk and Gyathuk
    • Momos: Steamed or fried dumplings, usually with a meat filling.
    • Saadheko: Spicy marinated chicken salad.
    • Gundruk Soup: A soup made from Gundruk, a fermented leafy green vegetable.
    • Sinki : A fermented radish tap-root product, traditionally consumed as a base for soup and as a pickle. Eerily similar to Kimchi.
  • While pork and beef are pretty common, finding vegetarian dishes is equally easy.
  • Staple: Dal-Bhat with Subzi. Rice is a lot more common than wheat (rice) possibly due to greater carb content and proximity to West Bengal, India s largest producer of Rice.
  • Good places to eat in Gangtok
    • Hamro Bhansa Ghar, Nimtho (Nepali)
    • Taste of Tibet
    • Dragon Wok (Chinese & Japanese)

Buddhism in Sikkim
  • Bayul Demojong (Sikkim), is the most sacred Land in the Himalayas as per the belief of the Northern Buddhists and various religious texts.
  • Sikkim was blessed by Guru Padmasambhava, the great Buddhist saint who visited Sikkim in the 8th century and consecrated the land.
  • However, Buddhism is said to have reached Sikkim only in the 17th century with the arrival of three Tibetan monks viz. Rigdzin Goedki Demthruchen, Mon Kathok Sonam Gyaltshen & Rigdzin Legden Je at Yuksom. Together, they established a Buddhist monastery.
  • In 1642 they crowned Phuntsog Namgyal as the first monarch of Sikkim and gave him the title of Chogyal, or Dharma Raja.
  • The faith became popular through its royal patronage and soon many villages had their own monastery.
  • Today Sikkim has over 200 monasteries.

Major monasteries
  • Rumtek Monastery, 20Km from Gangtok
  • Lingdum/Ranka Monastery, 17Km from Gangtok
  • Phodong Monastery, 28Km from Gangtok
  • Ralang Monastery, 10Km from Ravangla
  • Tsuklakhang Monastery, Royal Palace, Gangtok
  • Enchey Monastery, Gangtok
  • Tashiding Monastery, 35Km from Ravangla


Reaching Sikkim
  • Gangtok, being the capital, is easiest to reach amongst other regions, by public transport and shared cabs.
  • By Air:
    • Pakyong (PYG) :
      • Nearest airport from Gangtok (about 1 hour away)
      • Tabletop airport
      • Reserved cabs cost around INR 1200.
      • As of Apr 2021, the only flights to PYG are from IGI (Delhi) and CCU (Kolkata).
    • Bagdogra (IXB) :
      • About 20 minutes from Siliguri and 4 hours from Gangtok.
      • Larger airport with flights to most major Indian cities.
      • Reserved cabs cost about INR 3000. Shared cabs cost about INR 350.
  • By Train:
    • New Jalpaiguri (NJP) :
      • About 20 minutes from Siliguri and 4 hours from Gangtok.
      • Reserved cabs cost about INR 3000. Shared cabs from INR 350.
  • By Road:
    • NH10 connects Siliguri to Gangtok
    • If you can t find buses plying to Gangtok directly, reach Siliguri and then take a cab to Gangtok.
  • Sikkim Nationalised Transport Div. also runs hourly buses between Siliguri and Gangtok and daily buses on other common routes. They re cheaper than shared cabs.
  • Wizzride also operates shared cabs between Siliguri/Bagdogra/NJP, Gangtok and Darjeeling. They cost about the same as shared cabs but pack in half as many people in luxury cars (Innova, Xylo, etc.) and are hence more comfortable.

Gangtok
  • Time needed: 1D/1N
  • Places to visit:
    • Hanuman Tok
    • Ganesh Tok
    • Tashi View Point [6,800ft]
    • MG Marg
    • Sikkim Zoo
    • Gangtok Ropeway
    • Enchey Monastery
    • Tsuklakhang Palace & Monastery
  • Hostels: Tagalong Backpackers (would strongly recommend), Zostel Gangtok
  • Places to chill: Travel Cafe, Caf Live & Loud and Gangtok Groove
  • Places to shop: Lal Market and MG Marg

Getting Around
  • Taxis operate on a reserved or shared basis. In case of the latter, you can pool with other commuters your taxis will pick up and drop en-route.
  • Naturally shared taxis only operate on popular routes. The easiest way to get around Gangtok is to catch a shared cab from MG Marg.
  • Reserved taxis for Gangtok sightseeing cost around INR 1000-1500, depending upon the spots you d like to see
  • Key taxi/bus stands :
    • Deorali stand: For Darjeeling, Siliguri, Kalimpong
    • Vajra stand: For North & East Sikkim (Tsomgo Lake & Nathula)
    • Rumtek taxi: For Ravangla, Pelling, Namchi, Geyzing, Jorethang and Singtam.
Exploring Gangtok on an MTB

North Sikkim
  • The easiest & most economical way to explore North Sikkim is the 3D/2N package offered by shared-cab drivers.
  • This includes food, permits, cab rides and accommodation (1N in Lachen and 1N in Lachung)
  • The accommodation on both nights are at homestays with bare necessities, so keep your hopes low.
  • In the spirit of sustainable tourism, you ll be asked to discard single-use plastic bottles, so please carry a bottle that you can refill along the way.
  • Zero Point and Gurdongmer Lake are snow-capped throughout the year
3D/2N Shared-cab Package Itinerary
  • Day 1
    • Gangtok (10am) - Chungthang - Lachung (stay)
  • Day 2
    • Pre-lunch : Lachung (6am) - Yumthang Valley [12,139ft] - Zero Point - Lachung [15,300ft]
    • Post-lunch : Lachung - Chungthang - Lachen (stay)
  • Day 3
    • Pre-lunch : Lachen (5am) - Kala Patthar - Gurdongmer Lake [16,910ft] - Lachen
    • Post-lunch : Lachen - Chungthang - Gangtok (7pm)
  • This itinerary is idealistic and depends on the level of snowfall.
  • Some drivers might switch up Day 2 and 3 itineraries by visiting Lachen and then Lachung, depending upon the weather.
  • Areas beyond Lachen & Lachung are heavily militarized since the Indo-China border is only a few miles away.

East Sikkim

Zuluk and Silk Route
  • Time needed: 2D/1N
  • Zuluk [9,400ft] is a small hamlet with an excellent view of the eastern Himalayan range including the Kanchenjunga.
  • Was once a transit point to the historic Silk Route from Tibet (Lhasa) to India (West Bengal).
  • The drive from Gangtok to Zuluk takes at least four hours. Hence, it makes sense to spend the night at a homestay and space out your trip to Zuluk

Tsomgo Lake and Nathula
  • Time Needed : 1D
  • A Protected Area Permit is required to visit these places, due to their proximity to the Chinese border
  • Tsomgo/Chhangu Lake [12,313ft]
    • Glacial lake, 40 km from Gangtok.
    • Remains frozen during the winter season.
    • You can also ride on the back of a Yak for INR 300
  • Baba Mandir
    • An old temple dedicated to Baba Harbhajan Singh, a Sepoy in the 23rd Regiment, who died in 1962 near the Nathu La during Indo China war.
  • Nathula Pass [14,450ft]
    • Located on the Indo-Tibetan border crossing of the Old Silk Route, it is one of the three open trading posts between India and China.
    • Plays a key role in the Sino-Indian Trade and also serves as an official Border Personnel Meeting(BPM) Point.
    • May get cordoned off by the Indian Army in event of heavy snowfall or for other security reasons.


West Sikkim
  • Time needed: 3N/1N
  • Hostels at Pelling : Mochilerro Ostillo

Itinerary

Day 1: Gangtok - Ravangla - Pelling
  • Leave Gangtok early, for Ravangla through the Temi Tea Estate route.
  • Spend some time at the tea garden and then visit Buddha Park at Ravangla
  • Head to Pelling from Ravangla

Day 2: Pelling sightseeing
  • Hire a cab and visit Skywalk, Pemayangtse Monastery, Rabdentse Ruins, Kecheopalri Lake, Kanchenjunga Falls.

Day 3: Pelling - Gangtok/Siliguri
  • Wake up early to catch a glimpse of Kanchenjunga at the Pelling Helipad around sunrise
  • Head back to Gangtok on a shared-cab
  • You could take a bus/taxi back to Siliguri if Pelling is your last stop.

Darjeeling
  • In my opinion, Darjeeling is lovely for a two-day detour on your way back to Bagdogra/Siliguri and not any longer (unless you re a Bengali couple on a honeymoon)
  • Once a part of Sikkim, Darjeeling was ceded to the East India Company after a series of wars, with Sikkim briefly receiving a grant from EIC for gifting Darjeeling to the latter
  • Post-independence, Darjeeling was merged with the state of West Bengal.

Itinerary

Day 1 :
  • Take a cab from Gangtok to Darjeeling (shared-cabs cost INR 300 per seat)
  • Reach Darjeeling by noon and check in to your Hostel. I stayed at Hideout.
  • Spend the evening visiting either a monastery (or the Batasia Loop), Nehru Road and Mall Road.
  • Grab dinner at Glenary whilst listening to live music.

Day 2:
  • Wake up early to catch the sunrise and a glimpse of Kanchenjunga at Tiger Hill. Since Tiger Hill is 10km from Darjeeling and requires a permit, book your taxi in advance.
  • Alternatively, if you don t want to get up at 4am or shell out INR1500 on the cab to Tiger Hill, walk to the Kanchenjunga View Point down Mall Road
  • Next, queue up outside Keventers for breakfast with a view in a century-old cafe
  • Get a cab at Gandhi Road and visit a tea garden (Happy Valley is the closest) and the Ropeway. I was lucky to meet 6 other backpackers at my hostel and we ended up pooling the cab at INR 200 per person, with INR 1400 being on the expensive side, but you could bargain.
  • Get lunch, buy some tea at Golden Tips, pack your bags and hop on a shared-cab back to Siliguri. It took us about 4hrs to reach Siliguri, with an hour to spare before my train.
  • If you ve still got time on your hands, then check out the Peace Pagoda and the Darjeeling Himalayan Railway (Toy Train). At INR 1500, I found the latter to be too expensive and skipped it.


Tips and hacks
  • Download offline maps, especially when you re exploring Northern Sikkim.
  • Food and booze are the cheapest in Gangtok. Stash up before heading to other regions.
  • Keep your Aadhar/Passport handy since you need permits to travel to North & East Sikkim.
  • In rural areas and some cafes, you may get to try Rhododendron Wine, made from Rhododendron arboreum a.k.a Gurans. Its production is a little hush-hush since the flower is considered holy and is also the National Flower of Nepal.
  • If you don t want to invest in a new jacket, boots or a pair of gloves, you can always rent them at nominal rates from your hotel or little stores around tourist sites.
  • Check the weather of a region before heading there. Low visibility and precipitation can quite literally dampen your experience.
  • Keep your itinerary flexible to accommodate for rest and impromptu plans.
  • Shops and restaurants close by 8pm in Sikkim and Darjeeling. Plan for the same.

Carry
  • a couple of extra pairs of socks (woollen, if possible)
  • a pair of slippers to wear indoors
  • a reusable water bottle
  • an umbrella
  • a power bank
  • a couple of tablets of Diamox. Helps deal with altitude sickness
  • extra clothes and wet bags since you may not get a chance to wash/dry your clothes
  • a few passport size photographs

Shared-cab hacks
  • Intercity rides can be exhausting. If you can afford it, pay for an additional seat.
  • Call shotgun on the drives beyond Lachen and Lachung. The views are breathtaking.
  • Return cabs tend to be cheaper (WB cabs travelling from SK and vice-versa)

Cost
  • My median daily expenditure (back when I went to Sikkim in early March 2021) was INR 1350.
  • This includes stay (bunk bed), food, wine and transit (shared cabs)
  • In my defence, I splurged on food, wine and extra seats in shared cabs, but if you re on a budget, you could easily get by on INR 1 - 1.2k per day.
  • For a 9-day trip, I ended up shelling out nearly INR 15k, including 2AC trains to & from Kolkata
  • Note : Summer (March to May) and Autumn (October to December) are peak seasons, and thereby more expensive to travel around.

Souvenirs and things you should buy

Buddhist souvenirs :
  • Colourful Prayer Flags (great for tying on bikes or behind car windshields)
  • Miniature Prayer/Mani Wheels
  • Lucky Charms, Pendants and Key Chains
  • Cham Dance masks and robes
  • Singing Bowls
  • Common symbols: Om mani padme hum, Ashtamangala, Zodiac signs

Handicrafts & Handlooms
  • Tibetan Yak Wool shawls, scarfs and carpets
  • Sikkimese Ceramic cups
  • Thangka Paintings

Edibles
  • Darjeeling Tea (usually brewed and not boiled)
  • Wine (Arucha Peach & Rhododendron)
  • Dalle Khursani (Chilli) Paste and Pickle

Header Icon made by Freepik from www.flaticon.com is licensed by CC 3.0 BY

8 April 2021

Sean Whitton: consfigurator-live-build

One of my goals for Consfigurator is to make it capable of installing Debian to my laptop, so that I can stop booting to GRML and manually partitioning and debootstrapping a basic system, only to then turn to configuration management to set everything else up. My configuration management should be able to handle the partitioning and debootstrapping, too. The first stage was to make Consfigurator capable of debootstrapping a basic system, chrooting into it, and applying other arbitrary configuration, such as installing packages. That s been in place for some weeks now. It s sophisticated enough to avoid starting up newly installed services, but I still need to add some bind mounting. Another significant piece is teaching Consfigurator how to partition block devices. That s quite tricky to do in a sufficiently general way I want to cleanly support various combinations of LUKS, LVM and regular partitions, including populating /etc/crypttab and /etc/fstab. I have some ideas about how to do it, but it ll probably take a few tries to get the abstractions right. Let s imagine that code is all in place, such that Consfigurator can be pointed at a block device and it will install a bootable Debian system to it. Then to install Debian to my laptop I d just need to take my laptop s disk drive out and plug it into another system, and run Consfigurator on that system, as root, pointed at the block device representing my laptop s disk drive. For virtual machines, it would be easy to write code which loop-mounts an empty disk image, and then Consfigurator could be pointed at the loop-mounted block device, thereby making the disk image file bootable. This is adequate for virtual machines, or small single-board computers with tiny storage devices (not that I actually use any of those, but I want Consfigurator to be able to make disk images for them!). But it s not much good for my laptop. I casually referred to taking out my laptop s disk drive and connecting it to another computer, but this would void my laptop s warranty. And Consfigurator would not be able to update my laptop s NVRAM, as is needed on UEFI systems. What s wanted here is a live system which can run Consfigurator directly on the laptop, pointed at the block device representing its physical disk drive. Ideally this live system comes with a chroot with the root filesystem for the new Debian install already built, so that network access is not required, and all Consfigurator has to do is partition the drive and copy in the contents of the chroot. The live system could be set up to automatically start doing that upon boot, but another option is to just make Consfigurator itself available to be used interactively. The user boots the live system, starts up Emacs, starts up Lisp, and executes a Consfigurator deployment, supplying the block device representing the laptop s disk drive as an argument to the deployment. Consfigurator goes off and partitions that drive, copies in the contents of the chroot, and executes grub-install to make the laptop bootable. This is also much easier to debug than a live system which tries to start partitioning upon boot. It would look something like this:
    ;; melete.silentflame.com is a Consfigurator host object representing the
    ;; laptop, including information about the partitions it should have
    (deploy-these :local ...
      (chroot:partitioned-and-installed
        melete.silentflame.com "/srv/chroot/melete" "/dev/nvme0n1"))
Now, building live systems is a fair bit more involved than installing Debian to a disk drive and making it bootable, it turns out. While I want Consfigurator to be able to completely replace the Debian Installer, I decided that it is not worth trying to reimplement the relevant parts of the Debian Live tool suite, because I do not need to make arbitrary customisations to any live systems. I just need to have some packages installed and some files in place. Nevertheless, it is worth teaching Consfigurator how to invoke Debian Live, so that the customisation of the chroot which isn t just a matter of passing options to lb_config(1) can be done with Consfigurator. This is what I ve ended up with in Consfigurator s source code:
(defpropspec image-built :lisp (config dir properties)
  "Build an image under DIR using live-build(7), where the resulting live
system has PROPERTIES, which should contain, at a minimum, a property from
CONSFIGURATOR.PROPERTY.OS setting the Debian suite and architecture.  CONFIG
is a list of arguments to pass to lb_config(1), not including the '-a' and
'-d' options, which Consfigurator will supply based on PROPERTIES.
This property runs the lb_config(1), lb_bootstrap(1), lb_chroot(1) and
lb_binary(1) commands to build or rebuild the image.  Rebuilding occurs only
when changes to CONFIG or PROPERTIES mean that the image is potentially
out-of-date; e.g. if you just add some new items to PROPERTIES then in most
cases only lb_chroot(1) and lb_binary(1) will be re-run.
Note that lb_chroot(1) and lb_binary(1) both run after applying PROPERTIES,
and might undo some of their effects.  For example, to configure
/etc/apt/sources.list, you will need to use CONFIG not PROPERTIES."
  (:desc (declare (ignore config properties))
         #?"Debian Live image built in $ dir ")
  (let* (...)
    ;; ...
     (eseqprops
      ;; ...
      (on-change
          (eseqprops
           (on-change
               (file:has-content ,auto/config ,(auto/config config) :mode #o755)
             (file:does-not-exist ,@clean)
             (%lbconfig ,dir)
             (%lbbootstrap t ,dir))
           (%lbbootstrap nil ,dir)
           (deploys ((:chroot :into ,chroot)) ,host))
        (%lbchroot ,dir)
        (%lbbinary ,dir)))))
Here, %lbconfig is a property running lb_config(1), %lbbootstrap one which runs lb_bootstrap(1), etc. Those properties all just change directory to the right place and run the command, essentially, with a little extra code to handle failed debootstraps and the like. The ON-CHANGE and ESEQPROPS combinators work together to sequence the interaction of the Debian Live suite and Consfigurator. This way, we only rebuild the chroot if the configuration changed, and we only rebuild the image if the chroot changed. Now over in my personal consfig:
(try-register-data-source
 :git-snapshot :name "consfig" :repo #P"src/cl/consfig/" ...)
(defproplist hybrid-live-iso-built :lisp ()
  "Build a Debian Live system in /srv/live/spw.
Typically this property is not applied in a DEFHOST form, but rather run as
needed at the REPL.  The reason for this is that otherwise the whole image will
get rebuilt each time a commit is made to my dotfiles repo or to my consfig."
  (:desc "Sean's Debian Live system image built")
  (live-build:image-built.
      '("--archive-areas" "main contrib non-free" ...)
      "/srv/live/spw"
    (os:debian-stable "buster" :amd64)
    (basic-props)
    (apt:installed "whatever" "you" "want")
    (git:snapshot-extracted "/etc/skel/src" "dotfiles")
    (file:is-copy-of "/etc/skel/.bashrc" "/etc/skel/src/dotfiles/.bashrc")
    (git:snapshot-extracted "/root/src/cl" "consfig")))
The first argument to LIVE-BUILD:IMAGE-BUILT. is additional arguments to lb_config(1). The third argument onwards are the properties for the live system. The cool thing is GIT:SNAPSHOT-EXTRACTED the calls to this ensure that a copy of my Emacs configuration and my consfig end up in the live image, ready to be used interactively to install Debian, as described above. I ll need to add something like (chroot:host-chroot-bootstrapped melete.silentflame.com "/srv/chroot/melete") too. As with everything Consfigurator-related, Joey Hess s Propellor is the giant upon whose shoulders I m standing.

29 March 2021

Louis-Philippe V ronneau: Montreal 2021 BSP

Last weekend Debian Quebec held a Bug Squashing Party to try to fix some bugs in the upcoming Debian Bullseye. I wasn't convinced at first, but Tassia's contagious energy and willingness to help organise the event eventually won me over. And shockers! it was really fun. Group picture of the BSP attendees on Jitsi Meet We fixed a couple of RC bugs, held lightning talks and had a virtual pizza party! My lightning talk on autopkgtests was well received and a few people decided to migrate to sbuild and enable autopkgtests by default. Sergio's talk on debuginfod was incredibly interesting. I'm not a C programmer and the live demo made me understand how this service can help making debugging C easier. Jerome's talk on using Yubikeys to unlock LUKS encrypted drives was also very good! It also served as a reminder that Yubico's product are much more featureful and convenient to use than other Open Hardware/ Free Software hardware tokens. Hopefully that will change as enterprises like Nitrokey and Solokey mature. This was my third BSP, crazy how time flies... With the Bullseye release closing in, you should try to join or organise one!

16 January 2021

Abhijith PA: Transition from Thunderbird to Mutt

I was going OK with Thunderbird and enigmail(though it have many problems). Normally I go through changelogs before updating packages and rarely do a complete upgrage of my machine. Couple of days ago I did a complete upgrade of system which updated my Thunderbird to latest version and throwing of enigmail plugin for using their native openPGP support. There is a blog from Mozilla which I should ve read earlier. Thunderbird s builtin openPGP functionality is still in experimental, atleast not ready for my workflow. I could ve downgrade to version 68. But I chose to move to my secondary MUA, mutt. I was using mutt for emails and newsletters that I check twice in a year a so. So I started configuring mutt to handle my big mailboxes. It took three evenings to configure mutt to my workflow. Though the basic setup can be done in less than an hour it is the small nitpicks consumed much of my time. Currently I have isync to pull and keep mails offline. Mutt to read, msmtp to send, abook as the email address book and urlview to see the links in mail. I am still learning notmuch and virtual mailbox ways to filter. Mutt There are ton of articles out there to configure mutt and all related things to it. But I find certain configs very hard to get. So I will write down those. So far, everything going okay.

Cons
  • some times mbsync throws EOF and secret key not found error.
  • searching is still a pain in mutt
  • nano s spell checker also check things which I am replying to.

More to come Well for now I moved mail from part of the Thunderbird. But Thunderbird was more than a MUA to me. It was my RSS reader, calendar and to-do list manager. I will write more about those once I make a complete transition.

11 December 2020

Evgeni Golov: systemd + SELinux =

Okay, getting a title that will ensure clicks for this post was easy. Now comes the hard part: content! When you deploy The Foreman, you want a secure setup by default. That's why we ship (and enable) a SELinux policy which allows you to run the involved daemons in confined mode. We have recently switched our default Ruby application server from Passenger (running via mod_passenger inside Apache httpd) to Puma (running standalone and Apache just being a reverse proxy). While doing so, we initially deployed Puma listening on localhost:3000 and while localhost is pretty safe, a local user could still turn out evil and talk directly to Puma, pretending to be authenticated by Apache (think Kerberos or X.509 cert auth). Obviously, this is not optimal, so the next task was to switch Puma to listen on an UNIX socket and only allow Apache to talk to said socket. This doesn't sound overly complicated, and indeed it wasn't. The most time/thought was spent on doing that in a way that doesn't break existing setups and still allows binding to a TCP socket for setups where users explicitly want that. We also made a change to the SELinux policy to properly label the newly created socket and allow httpd to access it. The whole change was carefully tested on CentOS 7 and worked like a charm. So we merged it, and it broke. Only on CentOS 8, but broken is broken, right? This is the start of my Thanksgiving story "learn how to debug SELinux issues" ;) From the logs of our integration test I knew the issue was Apache not being able to talk to that new socket (we archive sos reports as part of the tests, and those clearly had it in the auditd logs). But I also knew we did prepare our policy for that change, so either our preparation was not sufficient or the policy wasn't properly loaded. The same sos report also contained the output of semanage fcontext --list which stated that all regular files called /run/foreman.sock would get the foreman_var_run_t type assigned. Wait a moment, all regular files?! A socket is not a regular file! Let's quickly make that truly all files. That clearly changed the semanage fcontext --list output, but the socket was still created as var_run_t?! It was time to actually boot a CentOS 8 VM and try more things out. Interestingly, you actually can't add a rule for /run/something, as /run is an alias (equivalency in SELinux speak) for /var/run:
# semanage fcontext --add -t foreman_var_run_t /run/foreman.sock
ValueError: File spec /run/foreman.sock conflicts with equivalency rule '/run /var/run'; Try adding '/var/run/foreman.sock' instead
I have no idea how the list output in the report got that /run rule, but okay, let's match /var/run/foreman.sock. Did that solve the issue? Of course not! And you knew it, as I didn't get to the juciest part of the headline yet: systemd! We use systemd to create the socket, as it is both convenient and useful (no more clients connecting before Rails has finished booting). But why is it wrongly labeling our freshly created socket?! A quick check with touch shows that the policy is correct now, the touched file gets the right type assigned. So it must be something with systemd A bit of poking (and good guesswork based on prior experience with a similar issue in Puppet: PUP-2169 and PUP-10548) led to the realization that a systemctl daemon-reexec after adding the file context rule "fixes" the issue. Moving the poking to Google, you quickly end up at systemd issue #9997 which is fixed in v245, but that's in no EL release yet. And indeed, the issue seems fixed on my Fedora 33 with systemd 246, but I still need it to work on CentOS 7 and 8 Well, maybe that reexec isn't that bad after all? At least the socket is now properly labeled and httpd can connect to it on CentOS 8. Btw, no idea why the connection worked on CentOS 7, as there the socket was also wrongly labeled, but SELinux didn't deny httpd to open it. Big shout out to lzap and ewoud for helping me with this beast!

5 October 2020

Reproducible Builds: Reproducible Builds in September 2020

Welcome to the September 2020 report from the Reproducible Builds project. In our monthly reports, we attempt to summarise the things that we have been up to over the past month, but if you are interested in contributing to the project, please visit our main website. This month, the Reproducible Builds project was pleased to announce a donation from Amateur Radio Digital Communications (ARDC) in support of its goals. ARDC s contribution will propel the Reproducible Builds project s efforts in ensuring the future health, security and sustainability of our increasingly digital society. Amateur Radio Digital Communications (ARDC) is a non-profit which was formed to further research and experimentation with digital communications using radio, with a goal of advancing the state of the art of amateur radio and to educate radio operators in these techniques. You can view the full announcement as well as more information about ARDC on their website.
In August s report, we announced that Jennifer Helsby (redshiftzero) launched a new reproduciblewheels.com website to address the lack of reproducibility of Python wheels . This month, Kushal Das posted a brief follow-up to provide an update on reproducible sources as well. The Threema privacy and security-oriented messaging application announced that within the next months , their apps will become fully open source, supporting reproducible builds :
This is to say that anyone will be able to independently review Threema s security and verify that the published source code corresponds to the downloaded app.
You can view the full announcement on Threema s website.

Events Sadly, due to the unprecedented events in 2020, there will be no in-person Reproducible Builds event this year. However, the Reproducible Builds project intends to resume meeting regularly on IRC, starting on Monday, October 12th at 18:00 UTC (full announcement). The cadence of these meetings will probably be every two weeks, although this will be discussed and decided on at the first meeting. (An editable agenda is available.) On 18th September, Bernhard M. Wiedemann gave a presentation in German titled Wie reproducible builds Software sicherer machen ( How reproducible builds make software more secure ) at the Internet Security Digital Days 2020 conference. (View video.) On Saturday 10th October, Morten Linderud will give a talk at Arch Conf Online 2020 on The State of Reproducible Builds in the Arch Linux distribution:
The previous year has seen great progress in Arch Linux to get reproducible builds in the hands of the users and developers. In this talk we will explore the current tooling that allows users to reproduce packages, the rebuilder software that has been written to check packages and the current issues in this space.
During the Reproducible Builds summit in Marrakesh, GNU Guix, NixOS and Debian were able to produce a bit-for-bit identical binary when building GNU Mes, despite using three different major versions of GCC. Since the summit, additional work resulted in a bit-for-bit identical Mes binary using tcc and this month, a fuller update was posted by the individuals involved.

Development work In openSUSE, Bernhard M. Wiedemann published his monthly Reproducible Builds status update.

Debian Chris Lamb uploaded a number of Debian packages to address reproducibility issues that he had previously provided patches for, including cfingerd (#831021), grap (#870573), splint (#924003) & schroot (#902804) Last month, an issue was identified where a large number of Debian .buildinfo build certificates had been tainted on the official Debian build servers, as these environments had files underneath the /usr/local/sbin directory to prevent the execution of system services during package builds. However, this month, Aurelien Jarno and Wouter Verhelst fixed this issue in varying ways, resulting in a special policy-rcd-declarative-deny-all package. Building on Chris Lamb s previous work on reproducible builds for Debian .ISO images, Roland Clobus announced his work in progress on making the Debian Live images reproducible. [ ] Lucas Nussbaum performed an archive-wide rebuild of packages to test enabling the reproducible=+fixfilepath Debian build flag by default. Enabling the fixfilepath feature will likely fix reproducibility issues in an estimated 500-700 packages. The test revealed only 33 packages (out of 30,000 in the archive) that fail to build with fixfilepath. Many of those will be fixed when the default LLVM/Clang version is upgraded. 79 reviews of Debian packages were added, 23 were updated and 17 were removed this month adding to our knowledge about identified issues. Chris Lamb added and categorised a number of new issue types, including packages that captures their build path via quicktest.h and absolute build directories in documentation generated by Doxygen , etc. Lastly, Lukas Puehringer s uploaded a new version of the in-toto to Debian which was sponsored by Holger Levsen. [ ]

diffoscope diffoscope is our in-depth and content-aware diff utility that can not only locate and diagnose reproducibility issues, it provides human-readable diffs of all kinds too. In September, Chris Lamb made the following changes to diffoscope, including preparing and uploading versions 159 and 160 to Debian:
  • New features:
    • Show ordering differences only in strings(1) output by applying the ordering check to all differences across the codebase. [ ]
  • Bug fixes:
    • Mark some PGP tests that they require pgpdump, and check that the associated binary is actually installed before attempting to run it. (#969753)
    • Don t raise exceptions when cleaning up after guestfs cleanup failure. [ ]
    • Ensure we check FALLBACK_FILE_EXTENSION_SUFFIX, otherwise we run pgpdump against all files that are recognised by file(1) as data. [ ]
  • Codebase improvements:
    • Add some documentation for the EXTERNAL_TOOLS dictionary. [ ]
    • Abstract out a variable we use a couple of times. [ ]
  • diffoscope.org website improvements:
    • Make the (long) demonstration GIF less prominent on the page. [ ]
In addition, Paul Spooren added support for automatically deploying Docker images. [ ]

Website and documentation This month, a number of updates to the main Reproducible Builds website and related documentation. Chris Lamb made the following changes: In addition, Holger Levsen re-added the documentation link to the top-level navigation [ ] and documented that the jekyll-polyglot package is required [ ]. Lastly, diffoscope.org and reproducible-builds.org were transferred to Software Freedom Conservancy. Many thanks to Brett Smith from Conservancy, J r my Bobbio (lunar) and Holger Levsen for their help with transferring and to Mattia Rizzolo for initiating this.

Upstream patches The Reproducible Builds project detects, dissects and attempts to fix as many currently-unreproducible packages as possible. We endeavour to send all of our patches upstream where appropriate. This month, we wrote a large number of these patches, including: Bernhard M. Wiedemann also reported issues in git2-rs, pyftpdlib, python-nbclient, python-pyzmq & python-sidpy.

Testing framework The Reproducible Builds project operates a Jenkins-based testing framework to power tests.reproducible-builds.org. This month, Holger Levsen made the following changes:
  • Debian:
    • Shorten the subject of nodes have gone offline notification emails. [ ]
    • Also track bugs that have been usertagged with usrmerge. [ ]
    • Drop abort-related codepaths as that functionality has been removed from Jenkins. [ ]
    • Update the frequency we update base images and status pages. [ ][ ][ ][ ]
  • Status summary view page:
    • Add support for monitoring systemctl status [ ] and the number of diffoscope processes [ ].
    • Show the total number of nodes [ ] and colourise critical disk space situations [ ].
    • Improve the visuals with respect to vertical space. [ ][ ]
  • Debian rebuilder prototype:
    • Resume building random packages again [ ] and update the frequency that packages are rebuilt. [ ][ ]
    • Use --no-respect-build-path parameter until sbuild 0.81 is available. [ ]
    • Treat the inability to locate some packages as a debrebuild problem, and not as a issue with the rebuilder itself. [ ]
  • Arch Linux:
    • Update various components to be compatible with Arch Linux s move to the xz compression format. [ ][ ][ ]
    • Allow scheduling of old packages to catch up on the backlog. [ ][ ][ ]
    • Improve formatting on the summary page. [ ][ ]
    • Update HTML pages once every hour, not every 30 minutes. [ ]
    • Use the Ubuntu (!) GPG keyserver to validate packages. [ ]
  • System health checks:
    • Highlight important bad conditions in colour. [ ][ ]
    • Add support for detecting more problems, including Jenkins shutdown issues [ ], failure to upgrade Arch Linux packages [ ], kernels with wrong permissions [ ], etc.
  • Misc:
    • Delete old schroot sessions after 2 days, not 3. [ ]
    • Use sudo to cleanup diffoscope schroot sessions. [ ]
In addition, stefan0xC fixed a query for unknown results in the handling of Arch Linux packages [ ] and Mattia Rizzolo updated the template that notifies maintainers by email of their newly-unreproducible packages to ensure that it did not get caught in junk/spam folders [ ]. Finally, build node maintenance was performed by Holger Levsen [ ][ ][ ][ ], Mattia Rizzolo [ ][ ] and Vagrant Cascadian [ ][ ][ ].
If you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. However, you can get in touch with us via:

9 September 2020

Reproducible Builds: Reproducible Builds in August 2020

Welcome to the August 2020 report from the Reproducible Builds project. In our monthly reports, we summarise the things that we have been up to over the past month. The motivation behind the Reproducible Builds effort is to ensure no flaws have been introduced from the original free software source code to the pre-compiled binaries we install on our systems. If you re interested in contributing to the project, please visit our main website.


This month, Jennifer Helsby launched a new reproduciblewheels.com website to address the lack of reproducibility of Python wheels. To quote Jennifer s accompanying explanatory blog post:
One hiccup we ve encountered in SecureDrop development is that not all Python wheels can be built reproducibly. We ship multiple (Python) projects in Debian packages, with Python dependencies included in those packages as wheels. In order for our Debian packages to be reproducible, we need that wheel build process to also be reproducible
Parallel to this, transparencylog.com was also launched, a service that verifies the contents of URLs against a publicly recorded cryptographic log. It keeps an append-only log of the cryptographic digests of all URLs it has seen. (GitHub repo) On 18th September, Bernhard M. Wiedemann will give a presentation in German, titled Wie reproducible builds Software sicherer machen ( How reproducible builds make software more secure ) at the Internet Security Digital Days 2020 conference.

Reproducible builds at DebConf20 There were a number of talks at the recent online-only DebConf20 conference on the topic of reproducible builds. Holger gave a talk titled Reproducing Bullseye in practice , focusing on independently verifying that the binaries distributed from ftp.debian.org are made from their claimed sources. It also served as a general update on the status of reproducible builds within Debian. The video (145 MB) and slides are available. There were also a number of other talks that involved Reproducible Builds too. For example, the Malayalam language mini-conference had a talk titled , ? ( I want to join Debian, what should I do? ) presented by Praveen Arimbrathodiyil, the Clojure Packaging Team BoF session led by Elana Hashman, as well as Where is Salsa CI right now? that was on the topic of Salsa, the collaborative development server that Debian uses to provide the necessary tools for package maintainers, packaging teams and so on. Jonathan Bustillos (Jathan) also gave a talk in Spanish titled Un camino verificable desde el origen hasta el binario ( A verifiable path from source to binary ). (Video, 88MB)

Development work After many years of development work, the compiler for the Rust programming language now generates reproducible binary code. This generated some general discussion on Reddit on the topic of reproducibility in general. Paul Spooren posted a request for comments to OpenWrt s openwrt-devel mailing list asking for clarification on when to raise the PKG_RELEASE identifier of a package. This is needed in order to successfully perform rebuilds in a reproducible builds context. In openSUSE, Bernhard M. Wiedemann published his monthly Reproducible Builds status update. Chris Lamb provided some comments and pointers on an upstream issue regarding the reproducibility of a Snap / SquashFS archive file. [ ]

Debian Holger Levsen identified that a large number of Debian .buildinfo build certificates have been tainted on the official Debian build servers, as these environments have files underneath the /usr/local/sbin directory [ ]. He also filed against bug for debrebuild after spotting that it can fail to download packages from snapshot.debian.org [ ]. This month, several issues were uncovered (or assisted) due to the efforts of reproducible builds. For instance, Debian bug #968710 was filed by Simon McVittie, which describes a problem with detached debug symbol files (required to generate a traceback) that is unlikely to have been discovered without reproducible builds. In addition, Jelmer Vernooij called attention that the new Debian Janitor tool is using the property of reproducibility (as well as diffoscope when applying archive-wide changes to Debian:
New merge proposals also include a link to the diffoscope diff between a vanilla build and the build with changes. Unfortunately these can be a bit noisy for packages that are not reproducible yet, due to the difference in build environment between the two builds. [ ]
56 reviews of Debian packages were added, 38 were updated and 24 were removed this month adding to our knowledge about identified issues. Specifically, Chris Lamb added and categorised the nondeterministic_version_generated_by_python_param and the lessc_nondeterministic_keys toolchain issues. [ ][ ] Holger Levsen sponsored Lukas Puehringer s upload of the python-securesystemslib pacage, which is a dependency of in-toto, a framework to secure the integrity of software supply chains. [ ] Lastly, Chris Lamb further refined his merge request against the debian-installer component to allow all arguments from sources.list files (such as [check-valid-until=no]) in order that we can test the reproducibility of the installer images on the Reproducible Builds own testing infrastructure and sent a ping to the team that maintains that code.

Upstream patches The Reproducible Builds project detects, dissects and attempts to fix as many currently-unreproducible packages as possible. We endeavour to send all of our patches upstream where appropriate. This month, we wrote a large number of these patches, including:

diffoscope diffoscope is our in-depth and content-aware diff utility that can not only locate and diagnose reproducibility issues, it provides human-readable diffs of all kinds. In August, Chris Lamb made the following changes to diffoscope, including preparing and uploading versions 155, 156, 157 and 158 to Debian:
  • New features:
    • Support extracting data of PGP signed data. (#214)
    • Try files named .pgp against pgpdump(1) to determine whether they are Pretty Good Privacy (PGP) files. (#211)
    • Support multiple options for all file extension matching. [ ]
  • Bug fixes:
    • Don t raise an exception when we encounter XML files with <!ENTITY> declarations inside the Document Type Definition (DTD), or when a DTD or entity references an external resource. (#212)
    • pgpdump(1) can successfully parse some binary files, so check that the parsed output contains something sensible before accepting it. [ ]
    • Temporarily drop gnumeric from the Debian build-dependencies as it has been removed from the testing distribution. (#968742)
    • Correctly use fallback_recognises to prevent matching .xsb binary XML files.
    • Correct identify signed PGP files as file(1) returns data . (#211)
  • Logging improvements:
    • Emit a message when ppudump version does not match our file header. [ ]
    • Don t use Python s repr(object) output in Calling external command messages. [ ]
    • Include the filename in the not identified by any comparator message. [ ]
  • Codebase improvements:
    • Bump Python requirement from 3.6 to 3.7. Most distributions are either shipping with Python 3.5 or 3.7, so supporting 3.6 is not only somewhat unnecessary but also cumbersome to test locally. [ ]
    • Drop some unused imports [ ], drop an unnecessary dictionary comprehensions [ ] and some unnecessary control flow [ ].
    • Correct typo of output in a comment. [ ]
  • Release process:
    • Move generation of debian/tests/control to an external script. [ ]
    • Add some URLs for the site that will appear on PyPI.org. [ ]
    • Update author and author email in setup.py for PyPI.org and similar. [ ]
  • Testsuite improvements:
    • Update PPU tests for compatibility with Free Pascal versions 3.2.0 or greater. (#968124)
    • Mark that our identification test for .ppu files requires ppudump version 3.2.0 or higher. [ ]
    • Add an assert_diff helper that loads and compares a fixture output. [ ][ ][ ][ ]
  • Misc:
In addition, Mattia Rizzolo documented in setup.py that diffoscope works with Python version 3.8 [ ] and Frazer Clews applied some Pylint suggestions [ ] and removed some deprecated methods [ ].

Website This month, Chris Lamb updated the main Reproducible Builds website and documentation to:
  • Clarify & fix a few entries on the who page [ ][ ] and ensure that images do not get to large on some viewports [ ].
  • Clarify use of a pronoun re. Conservancy. [ ]
  • Use View all our monthly reports over View all monthly reports . [ ]
  • Move a is a suffix out of the link target on the SOURCE_DATE_EPOCH age. [ ]
In addition, Javier Jard n added the freedesktop-sdk project [ ] and Kushal Das added SecureDrop project [ ] to our projects page. Lastly, Michael P hn added internationalisation and translation support with help from Hans-Christoph Steiner [ ].

Testing framework The Reproducible Builds project operate a Jenkins-based testing framework to power tests.reproducible-builds.org. This month, Holger Levsen made the following changes:
  • System health checks:
    • Improve explanation how the status and scores are calculated. [ ][ ]
    • Update and condense view of detected issues. [ ][ ]
    • Query the canonical configuration file to determine whether a job is disabled instead of duplicating/hardcoding this. [ ]
    • Detect several problems when updating the status of reporting-oriented metapackage sets. [ ]
    • Detect when diffoscope is not installable [ ] and failures in DNS resolution [ ].
  • Debian:
    • Update the URL to the Debian security team bug tracker s Git repository. [ ]
    • Reschedule the unstable and bullseye distributions often for the arm64 architecture. [ ]
    • Schedule buster less often for armhf. [ ][ ][ ]
    • Force the build of certain packages in the work-in-progress package rebuilder. [ ][ ]
    • Only update the stretch and buster base build images when necessary. [ ]
  • Other distributions:
    • For F-Droid, trigger jobs by commits, not by a timer. [ ]
    • Disable the Archlinux HTML page generation job as it has never worked. [ ]
    • Disable the alternative OpenWrt rebuilder jobs. [ ]
  • Misc;
Many other changes were made too, including:
  • Chris Lamb:
    • Use <pre> HTML tags when dumping fixed-width debugging data in the self-serve package scheduler. [ ]
  • Mattia Rizzolo:
  • Vagrant Cascadian:
    • Mark that the u-boot Universal Boot Loader should not build architecture independent packages on the arm64 architecture anymore. [ ]
Finally, build node maintenance was performed by Holger Levsen [ ], Mattia Rizzolo [ ][ ] and Vagrant Cascadian [ ][ ][ ][ ]

Mailing list On our mailing list this month, Leo Wandersleb sent a message to the list after he was wondering how to expand his WalletScrutiny.com project (which aims to improve the security of Bitcoin wallets) from Android wallets to also monitor Linux wallets as well:
If you think you know how to spread the word about reproducibility in the context of Bitcoin wallets through WalletScrutiny, your contributions are highly welcome on this PR [ ]
Julien Lepiller posted to the list linking to a blog post by Tavis Ormandy titled You don t need reproducible builds. Morten Linderud (foxboron) responded with a clear rebuttal that Tavis was only considering the narrow use-case of proprietary vendors and closed-source software. He additionally noted that the criticism that reproducible builds cannot prevent against backdoors being deliberately introduced into the upstream source ( bugdoors ) are decidedly (and deliberately) outside the scope of reproducible builds to begin with. Chris Lamb included the Reproducible Builds mailing list in a wider discussion regarding a tentative proposal to include .buildinfo files in .deb packages, adding his remarks regarding requiring a custom tool in order to determine whether generated build artifacts are identical in a reproducible context. [ ] Jonathan Bustillos (Jathan) posted a quick email to the list requesting whether there was a list of To do tasks in Reproducible Builds. Lastly, Chris Lamb responded at length to a query regarding the status of reproducible builds for Debian ISO or installation images. He noted that most of the technical work has been performed but there are at least four issues until they can be generally advertised as such . He pointed that the privacy-oriented Tails operation system, which is based directly on Debian, has had reproducible builds for a number of years now. [ ]

If you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. However, you can get in touch with us via:

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