Search Results: "ron"

27 August 2011

Axel Beckert: Useful but Unknown Unix Tools: Calculating with IPs

There are two small CLI tools I need often when I m handling larger networks or more than a few IP addresses at once: netmask netmask is very handy for calculating with netmasks (anyone expected something else? ;-) in all variants:
$ netmask 192.168.96.0/255.255.248.0
    192.168.96.0/21
$ netmask -s 192.168.96.0/21
    192.168.96.0/255.255.248.0  
$ netmask --range 192.168.96.0/21
    192.168.96.0-192.168.103.255  (2048)
$ netmask 192.168.96.0:192.168.103.255
    192.168.96.0/21
$ netmask 192.168.87.0:192.168.110.255
    192.168.87.0/24
    192.168.88.0/21
    192.168.96.0/21
   192.168.104.0/22
   192.168.108.0/23
   192.168.110.0/24
$ netmask --cisco 192.168.96.0/21
    192.168.96.0 0.0.7.255
(The IP ranges in RFC5737 where too small for the examples I had in mind. :-) There s though one thing netmask can t do out of the box and that s where the second tool comes into play: prips When I read the package name prips, I always think of something like print postscript or so, but it s actually an abbreviation for print IPs . And that s all it does:
$ prips 192.0.2.0/29
192.0.2.0
192.0.2.1
192.0.2.2
192.0.2.3
192.0.2.4
192.0.2.5
192.0.2.6
192.0.2.7
$ prips 198.51.100.1 198.51.100.6
198.51.100.1
198.51.100.2
198.51.100.3
198.51.100.4
198.51.100.5
198.51.100.6
$ prips -i 2 203.0.113.0/28
203.0.113.0
203.0.113.2
203.0.113.4
203.0.113.6
203.0.113.8
203.0.113.10
203.0.113.12
203.0.113.14
$ prips -f hex 192.0.2.8/29
c0000208
c0000209
c000020a
c000020b
c000020c
c000020d
c000020e
c000020f
prips has proven to be very useful in combination with shell loops like these:
$ prips 192.0.2.0/29   xargs -n 1 host
[ ]
$ for ip in  prips 198.51.100.1 198.51.100.6 ; do host $ip; done
[ ]
And since prips doesn t support the 192.0.2.0/255.255.255.248 netmask syntax, you can even easily combine those two tools:
$ prips  netmask 192.0.2.0/255.255.255.248 
[ ]
(Hah! Now I was able to use RFC5737 IP ranges! ;-)

26 August 2011

Luca Bruno: OpenOCD and the Bus Pirate

As an enthusiast Open Hardware supporter, I regularly read the always brilliant Dangerous Prototype blog.
Last week it featured a short but complete tutorial about unbricking a Seagate Dockstar with OpenOCD and the Bus Pirate. The Bus Pirate is an open source hacker multi-tool that talks to electronic stuff, and which can be used as a JTAG adaptor (and much more!).
OpenOCD, the widespread free JTAG debugger, recently gained support for it. The good news is that, after almost a year and half of development, OpenOCD 0.5.0 has been finally released and is currently available in both Debian testing and unstable. Get it from the repository while it is hot, no need to fiddle with autotools and build tools anymore :) As a side-note for interested parties, SWD (Serial Wire Debugging) support is currently under development, along with its companion library (libswd). Hack and enjoy!

Axel Beckert: Useful but Unknown Unix Tools: Kill all processes of a user

I already got mails like What a pity that your nice blog posting series ended . No, it didn t end. As announced, I knew that I won t be able to keep up a daily schedule. It worked as long as I had already written the postings in advanced. But in the end the last postings were already written just in time and then I ran out of leisure and muse for a time. But as I said: It didn t end, it will be continued. And this is the next such posting. Oh, and for those who tell me further tools, I should blog about: I appreciate that, especially because that way I also hear about tools I didn t know about. But why just telling me and not blogging yourself about it? :-) At least those whose blog is part of Planet Debian or Planet Symlink anyway really should do this themselves. I d really like to see also others writing about cool tools. I neither have a right on the idea nor on the name of this series (call it meme if you want :-), so please go on and publish your favourite tools in a blog posting, too. :-) And for all those who want to join me and Myon blogging about cool Unix tools, independent if listed on Planet Debian or Planet Symlink, I encourage you to offer a separate feed for this kind of postings and join us on Planet Commandline. Anyway, here s the next such posting: As system administrator you often have the case that you have to kill all processes of one user, e.g. if a daemon didn t properly shut down itself or amok running leftovers of a GUI session. Many use pkill -SIGNAL -u user from the procps package or killall -SIGNAL -u user from the psmisc package for it. But that s a) quite cumbersome to type and b) is there a chance to forget about the -u and then bad things may happen, especially with pkill s default substring match, so I prefer another tool with a more explicit name:

slay slay has an easy to remember name (at least for BOFHs ;-) which is even quicker to type (alternating one character with the left and the right hand, at least on US layout keyboards) than pkill (all characters to type with the right hand), and has the same easy to remember commandline syntax like kill itself:
slay -SIGNAL user [user  ]
But beware, slay is

not only for BOFHs, but also from a BOFH It has a mean mode which is activated by default. With mean mode on, it won t kill the given user but the user who called the program if it is invoked as an ordinary user without root rights. *g* Interestingly I never ran into this issue despite I use this program often and for many years now. But some Ubuntu users did, probably because adding a sudo in front of some command is easier to forget than doing an ssh root@localhost or su - beforehand. They even seem to be so desperate about it that they forwarded the issue from Launchpad to the Debian Bug Tracking System. ;-) But to be honest even if I was very amused about those bug reports isn t this issue grave , as it causes very likely (unexpected) data loss?

Now playing: Monzy kill dash nine ( and your process is mine ;-)

25 August 2011

Bastian Venthur: KDE4 s annoying taskbar

Dear Lazyweb, since KDE4 is in unstable, the taskbar behaves very annoyingly when working with two monitors with different resolutions. I have a laptop. When I m at work, I put it into a docking station which is connected to a huge monitor. I m not working with dualhead or something, I m just using the huge monitor at work and the laptop s screen at home. I always want the taskbar to be maximized. The problem is, that KDE s taskbar fails to adjust the size of the taskbar correctly: Starting KDE at work, the taskbar is always too small (as wide as the laptop s monitor) and my first task is to maximize the taskbar. Starting KDE when I m back home, the taskbar is too wide (as wide as the external monitor s size) for the smaller monitor and I have to (ironically) maximize it again to fit on the now smaller monitor. Note that I m not using suspend or something. I m booting the laptop with the big screen connected or not. I also had that problem with KDE3, but that was fixed upstream long time ago. Has anyone a solution how to avoid this problem?

John Goerzen: Weather Station Excitement

I ve sort of wanted a weather station for a long time. Lately, the ham radio hobby has intensified that, and I finally got one. When I finally got the serial link cable yesterday, well I was perhaps irrationally excited. Terah accused me of running all around the house while gathering up stuff for it. That probably wasn t too inaccurate. Anyhow, here s the sensor suite. The station is a Davis Vantage Vue, and they have pictures of the included receiving console on their site. On the upper left is the anemometer (wind speed sensor). Next to that is the rain collector for the rain sensor. There is a solar panel on the front for power, and underneath that is the wind direction sensor. The white thing underneath the back is the temperature and humidity sensor, which is inside a radiation shield. There is also a barometer in there someplace. The indoor console receives the data via a 900MHz wireless link. The console can also be connected via a serial, USB, or Ethernet link to a PC. All sorts of software can then do all sorts of things with it. The console itself, though, keeps a history, has hi/low reports, graphs, and current condition display that is quite useful already. But if course I d want it hooked up to a computer. I figured I couldn t put the console in the basement next to the server due to wireless signal strength issues, but also didn t want to require my desktop PC to be up for this to work. So I ordered the serial version, and some cheap DB9 to RJ45 adapter jacks. I have CAT6 strung throughout the house, so I simply converted a surplus Ethernet port to a serial port and it worked beautifully. There are a ton of weather-related programs out there. My requirements said that I wanted something that runs on Linux. Options there include wview, vanprod, RRD Weather Graphs, Weewx, Meteo, and the commercial non-free Weather Display. That s quite a few choices. Of those, wview had the best support for various devices from various manufacturers, which I figure might be important down the road. It can directly generate detailed weather webpages. It can also submit data to Weather Underground. Weather Underground has a feature called rapid fire which lets viewers screens update with current observations every few seconds. None of the noncommercial programs supported it, so I added it to wview. With my tree, it s now sending Rapid Fire updates. It also can submit data to the Citizen Weather Observer Program, which provides a way to both share it with others and provide it to forecasters at the National Weather Service and university researchers. It gets processed by their ingest system and is quality checked against their computerized QC metrics. Jacob has enjoyed this he got into assembling it, and often wants to go see if the anemometer is spinning. And I was surprised to kind of enjoy working with C again. Perhaps that was because I didn t have to touch malloc() even once?

24 August 2011

Christian Perrier: 10 years being Debian Developer - part 2: before 1992-1994 - the switch

So, we stopped our very boring story around 1992. Let's summarize where I was at that moment: We're in 1992. Magali is about to come. Three children, from 0 to 4. I'm getting bored of these BBS things. OK, I did fun things like translating (eh) the documentation of Frontdoor a Fidonet node system written by a norwegian dude. But, still. Among my BBS friends, Ren is now playing regularly with a strange thing coming from Finland. This is pretty much like these mysterious "Unix" machines I hear about, sometimes at Onera, ran by strange wizards that often look like hippies from the 70's (hey...these were my youth years). I also have these few friends from the BBS world who are also playing with these thingies. Ollivier, noticeably, who is using of these mysterious @frmug.fr.net "email" addresses, from his PC running 386BSD (what? A PC not running those wonderful MS-DOS programs? How weird). Ren is apparently playing with another tribe. He often talks about an evolution of Minix written by a Finnish student, which is available with source code, just like Ren programs. Ren is also a member of that FrMug tribe, the FRench Minix Users Group, who are comunicating with "newsgroups" that are apparently similar to what we're doing with our BBS....but apparently more funnily hackish...and most often in that mysterious "U**x" world. Ah, that thing is called Linux. You can download it by FTP on "the Internet". But I don't have "the Internet". Oh, sure, we have this thing called BitNet at work, I even have what they call "an email address" as perrier@froner81.bitnet. We can maybe do things with that. Ah yes, there are funny tools that allow "downloading" files on "FTP" (WTH is that?) servers but doing that by mail. You receive dozenes of mails "uuencoded" (WTH is that? I'm not using Unix, I'm using Dos...but, eh, it works, still). Oh, fun, I now downloaded a full set of disks (14....I need to find 14 floppies, doh!) of something called Slackware. Apparently, a crazy freak, somewhere, did assemble things so that it's easy for dummies like me to install "a Linux machine". What? This 386 DX/16 PC I borrowed from my lab could be something like one of these very very very mysterious and expensive Sun machines that a few very bearded and very smelly dudes are using at Onera to perform high performance calculations? I have to do this. Not growing a beard, but install Linux. I could even "read mail" on them. Doh, I could even read those mysterious "newsgroups", that look like our Fidonet "conferences", the only difference being. All this is so interesting. So, at first, let's help my friend Ren to spread out this marvel to the world. Ren did setup his "Renux" box for this and everybody can access it through this very modern UUCP technology, to download Slackware disk images, last versions of the Linux kernel (direct from ftp.ibp.fr, thanks to another pionneer, R my Card....ext2fs author). So, I did setup an incredibly weird system to "download" this stuff by FTPmail, de-uuencode it, process it on my work machine and then re-upload it to my home BBS and make it available in one of the first "Linux" sections of French BBS. Yay. Even of my BBS machine is not running this wonder. Still, gradually, I was becoming bored of this BBS stuff. The sirens of open systems were constantly singing in my ears and the amount of work to put in running a Fidonet node wasn't really motivating for me anymore. Finally, after our daughter Magali was born, in March 1992, I decided to shut down my BBS....and just run as a Fidonet "point" (a personal system not opened to the public) and gradually switched my interest to these open systems. I thus ended running an "experimental" Linux system at work on this refurbished 386DX machine, already and playing between both worlds for about 18 months. At some point, around mid-1993, it became obvious to me that I more wanted to participate to newsgroups-style communication, participate to the advent of this Linux thing and learn things about what was to become "The Internet" (understand "the web", aha). Meanwhile, Ren did great work translating "The Linux System" by this guy, Matt Welsh, making The Thing accessible to dummies like me. So, after summer, I decided it was time to move on and shutdown this Fidonet thing and build something like my "Freenix" friends were running, and be able to download news and mail by UUCP, with my fast HST modem, and process them with Real Men tools such as inn, sendmail, pine and trn. And then, around October 1993, here I come ready to install a Linux machine at home, and therefore zap a few years of BBS stuff on my 40MB hard disk. But, eh, I just read about this shiny new thing named Debian, that was just announced a few weeks ago. It seems to be meant for dummies like me who need a little bit more than tarballs of binary code and have no clue about libraries, ABI and such mysterious things that apparenyl constantly lead to "core dumps" on my work experimental Slackware machine. Also, I don't really understand everything to what these dude says in his "Manifesto" but that seems interesting and his (their? dunno) thing seem easy to use. Let's download the 0.93whatever version of this thing and put this on a big set of floppies. A few days after, voil . I have my first Linux system at home and it is running that Debian thing. It will need several weeks of poking around documentations, playing weird things with INN and sendmail without understanding a s**t of both....and a lot of help from Freenix friends....and I end up with a working machine that can call out FrMug for UUCP downloads of mail and news and then feed local sendmail and INN servers with them and then allow the "bubulle" user to read them remotely...from his Windows machine. Yay, admitedly, I spent a few years still using a Windows machine for mail and news! How to say that? At that time, the GUI environments were a little bit rustic and, anyway, there was no point-and-click programs for mail and news. In the meantime, the machine got upgraded to Debian 1.1 by reinstalling the system. "kheops" was born....and so was bubulle@kheops.frmug.fr.net. We're probably around early 1994 and I'm running my first Debian server at home. The beard didn't grew up, I'm not eating pizzas all day long (but I drink beer) and I'm even practicing physical activities (I was a volleyball player at that time). Despite all these flaws, I'm turning into a geek, slowly. In next episode, you'll learn how I ended up dropping the use of Windows, compiling some free software and contributing to my first package. These will be "the genealogy years".

23 August 2011

Dirk Eddelbuettel: Accelerating path-dependent loops: A quick Rcpp case study

User BobH asked on StackOverflow about accelerating path-dependent loops. He provided a simple example in which a vector gets filled conditional on the value of the preceding element. Simple to code, but hard to vectorise. By the time I saw that question yesterday evening, Josh Ulrich had already posted a nice answer suggesting to switch from ifelse to if to escape the overhead of a vectorised expression on simple scalars. I meekly added a comment suggesting that Rcpp would likely do well on this and that someone should volunteer such an answer. Well, it is still August and Mr. Someone is on holiday, so this morning I followed up with such an answer. And as it turns out to work quite well indeed, we will repost it here. Let's start with the general setup, and the two functions supplied by Josh. We also byte-compile these using the compiler package which is the culmination of several years of work by R core member Luke Tierney. This package was added to R during the last major release, and we assessed it in this earlier blog post as well as several Rcpp-related follow-ups. We also load the packages for on-the-fly 'inline' compilation and easy benchmarking:
library(inline)
library(rbenchmark)
library(compiler)
fun1 <- function(z)  
  for(i in 2:NROW(z))  
    z[i] <- ifelse(z[i-1]==1, 1, 0)
   
  z
 
fun1c <- cmpfun(fun1)
fun2 <- function(z)  
  for(i in 2:NROW(z))  
    z[i] <- if(z[i-1]==1) 1 else 0
   
  z
 
fun2c <- cmpfun(fun2)
We see that basic worker just assign to the i-th element based on the preceding element. Function two uses the aforementioned if statement, and both are also byte-compiled. Writing the same code in C++ using both Rcpp (for the R/C++ integration) and inline for the on-the-fly compilation, linking and loading of C++ code into R is pretty straightforward too:
funRcpp <- cxxfunction(signature(zs="numeric"), plugin="Rcpp", body="
  Rcpp::NumericVector z = Rcpp::NumericVector(zs);
  int n = z.size();
  for (int i=1; i<n; i++)  
    z[i] = (z[i-1]==1.0 ? 1.0 : 0.0);
   
  return(z);
")
This single R function call takes the code embedded in the argument to the body variable, builds a complete function in temporary file, and then compiles, links and loads it. We can now call funRcpp() just like the other four functions and do so via the benchmark() function of the rbenchmark package.
R> z <- rep(c(1,1,0,0,0,0), 100)
R> identical(fun1(z),fun2(z),fun1c(z),fun2c(z),funRcpp(z))
[1] TRUE
R> 
R> res <- benchmark(fun1(z), fun2(z),
+                  fun1c(z), fun2c(z),
+                  funRcpp(z),
+                  columns=c("test", "replications", "elapsed", "relative", "user.self", "sys.self"),
+                  order="relative",
+                  replications=1000)
R> print(res)
        test replications elapsed relative user.self sys.self
5 funRcpp(z)         1000   0.005      1.0      0.01        0
4   fun2c(z)         1000   0.482     96.4      0.48        0
2    fun2(z)         1000   1.989    397.8      1.98        0
3   fun1c(z)         1000  11.365   2273.0     11.37        0
1    fun1(z)         1000  13.210   2642.0     13.21        0
We can focus on the columns labelled elapsed and relative. The C++ version is faster by a factor of almost one-hundred compared to the byte-compiled version of funtion2, and almost four-hundred times faster than the plain-R variant of function2. And function1 is even worse, coming at well over twenty-two-hundred times the run-time of the C++ version. Byte-compilation also helps little here. For comparison, we also ran the original example of a very short vector, called more frequently:
R> z <- c(1,1,0,0,0,0)
R> res2 <- benchmark(fun1(z), fun2(z),
+                  fun1c(z), fun2c(z),
+                  funRcpp(z),
+                  columns=c("test", "replications", "elapsed", "relative", "user.self", "sys.self"),
+                  order="relative",
+                  replications=10000)
R> print(res2)
        test replications elapsed relative user.self sys.self
5 funRcpp(z)        10000   0.047  1.00000      0.04        0
4   fun2c(z)        10000   0.134  2.85106      0.13        0
2    fun2(z)        10000   0.328  6.97872      0.32        0
3   fun1c(z)        10000   1.080 22.97872      1.08        0
1    fun1(z)        10000   1.243 26.44681      1.24        0
The qualitative ranking is unchanged: the Rcpp version dominates. Function2 using if instead of the vectorised ifelse is second-best with the byte-compiled version being about twice as fast that the plain R variant, but still almost three times slower than the C++ version. And the relative differences are less pronounced: relatively speaking, the function call overhead matters less here and the actual looping matters more: C++ gets a bigger advantage on the actual loop operations in the longer vectors. That it is an important result as it suggests that on more real-life sized data, the compiled version may reap a larger benefit. All in all a nice demonstration of Rcpp, and a gain of almost one-hundred to the best byte-compiled version is nothing to sneeze at---especially when it is so easy to write and load a five-line C++ function thanks to Rcpp. Before closing, a quick reminder that I will giving two classes on Rcpp in a few weeks. These will be in New York on September 24, and San Franciso on October 8, see this blog post as well as this page at Revolution Analytics (who are a co-organiser of the classes) for details and registration information.

Nathan Handler: Google Summer of Code Report #5

This is my fifth and final report about dextools for the 2011 Google Summer of Code program. During the summer, I worked with Matt Zimmerman and Stefano Zacchiroli to create a replacement web dashboard for the Debian Derivatives Exchange (DEX). The dashboard displays a list of projects and their respective tasks and then allows users to easily update the status of these tasks. The dashboard also contains two graphs for tracking the progress of projects and providing instant recognition of all contributions to a project. At the start of the summer, I knew that I wanted to to work on improving the DEX infrastructure. I had worked with the team on the ancient-merges project, and while a lot of good work was accomplished, the process for tracking our progress was a bit clunky and difficult to interact with. Anyone who read my initial proposal for the Summer of Code would probably agree that it was quite vague. I really did not have a solid plan for what I wanted to accomplish. This began to change after my initial phone call with my mentor, Matt Zimmerman. We decided that the first thing I would work on would be a basic dashboard. Our plan was to have all of the data stored on the Debian BTS. This would allow Debian Maintainers to benefit from DEX without needing to learn about DEX s tools and workflows. The dashboard would support multiple derivatives and multiple projects for each derivative. Each project would be made up of a list of tasks, where each task is linked to a BTS bug. I prepared a mockup and some initial code based on that plan. The dashboard was able to successfully display a list of BTS bugs and their information. It generated the lists by assuming that bugs would be usertagged with a user of debian-derivatives@lists.debian.org and a tag in the format of dex
. At this point, we started trying to make sure that the dashboard would work for things like the ancient-patches, python2.7, and the upcoming large-merges projects. It did not take long to determine that it would not work for all of these things. The ancient-patches project started with a simple list of patch names. While most of these patches eventually ended up as bugs on the BTS, they did not start this way. The dashboard would need to support specifying a list of task names. This meant that it would also need to store data itself and that not all data could be located on the BTS. This is when we first started to define what a task is. The dashboard tracks tasks. It does not directly track bugs or patches. A task is nothing more than a title and status with an optional assignee, note, and bug. This made it simple to convert a list of patch names or a list of bug numbers to a list of tasks. During the early early stages of the project, the dashboard moved around a lot. We hoped to have it end up on dex.alioth.debian.org, but we were not sure whether Alioth would meet all of our needs. This was right around the time of the Alioth migration. Thanks to some tips, I figured out that I could use a simple cronjob on wagner to pull the git repository for vasks. This would allow the running instance of the dashboard to always be up-to-date. The Alioth admins have also been quite supportive. They have installed several additional packages for me that were necessary to keep the dashboard running. From the start, Matt felt it was important to have some public documentation about the project. This would allow us to point people to something other than my blog posts. I decided to put this information on the wiki. At one point, I also had a copy of the wiki page stored in the git repository. This file was updated via a cronjob, and I then committed and pushed it when I had code changes. I ultimately decided that the best approach would be to maintain the page on the wiki. A basic README file is included in the git repository that simply links to the wiki page. On wagner, I have a cronjob running to pull a copy of the wiki page so that it can be accessed via the web. Since Matt was traveling/moving this Summer, he arranged for Stefano Zacchiroli to fill in for him as my mentor temporarily. It was at this point in the summer that I began working on the first graph script. The goal was to have a script to parse the list of tasks and generate a graph showing the number of open tasks versus time. This would allow us to easily track our progress, estimate when a project will be complete, and detect periods of slowing down. We decided that while we liked the Ubuntu burndown charts, they were a bit more complex than we needed, so we did not reuse their code. A dashboard that can t be modified is not that useful. An early goal of this project was to allow users to update the dashboard via the web. This proved to be a bit more difficult than I initially thought. First, all of the html files that make up the dashboard are generated by a script. This means that if you modify one of the html files directly, all changes will be lost the next time the script runs. When you make a change on a web form and hit submit, you usually expect to see the changes the next time you visit the page. In order to accomplish this, I made the form processing script directly modify the html files. However, at this point, we did not have a way to locally store extended information about tasks, causing the python script to delete all changes made via the web form. This issue was rectified fairly quickly. There is now a changes file that stores all information submitted via the web form. The python script reads this file and applies the changes when it is generating the html files. A second problem concerned the text inputs that were being used in most of the cells on the table. By default, some fields would have text cut-off if the string was too long. Text inputs have a size attribute that is meant to specify the number of visible characters. I attempted to set this attribute in a script to the length of the input s value. Strangely, the inputs ended up with a lot of extra whitespace following the text. This resulted in the table being stretched horizontally. After many hours of research and testing, I was unable to find a solution to this problem. We ultimately decided to simply remove the size attribute and accept that text will be cut-off. My code got some early testing from Allison Randal and other people working on the dex-ubuntu-python2.7 project. They were a huge help in providing feedback and finding bugs in the code. While the dashboard was unable to meet all of their needs (due to being in the early stages of development), I hope that it at least helped to make it easier to track the project s status. Whenever a script is accepting input from a user, it is important to validate it. Although the dashboard uses a select box to limit the choices for the status , it is still trivial to submit an arbitrary status for a task. That is why I added some validation to the form processing script. It will ignore any unknown values, ensuring that all tasks have a valid status. The other fields are a bit more tricky. They were designed to be arbitrary text fields. As a result, almost anything can be entered. There is no way to tell if something is a title or a person. We thought of a few ways we could change this, but most of them involved locking down the dashboard and restricting changes. The old dashboard treated the fields as arbitrary text, so we decided to not include any validation in the new one. One popular feature request was the ability to link directly to a project. Early versions of the dashboard had one main dex.html page that used javascript to pull in the various projects. To get around this, I first trying using the query string to allow users to specify a distribution and project. While this worked, it resulted in long and ugly URLs. It took a while for me to be able to implement a cleaner solution. However, I eventually split each project into its own static HTML file. This meant that people could simply copy the URL from the address bar to link to a particular project. The main reason for doing this was that we felt the typical person would be interested in working on a specific project; most people won t be interested in navigating between the different projects. This change also allowed links that utilized the #graph anchor to function properly. Before, due to the way the page went about loading the project, trying to specify a specific project and #graph in the URL did not work properly. There is a plugin for jquery that allows tables to be sorted by particular columns. For tables that just contain text, this works fine without any issues. However, once I started using select boxes and text inputs, things got a bit messed up. After some research, I finally figured out how to use addParser to instruct the tablesorter plugin in how to sort each column in the table. In some of the earlier versions, I used some zebra stripes to make the table easy to read. Thanks to a suggestion from Paul Wise (pabs), I got rid of this striping and modified the code to color the rows based on the task s status. Complete tasks are green, in progress tasks are yellow, and incomplete tasks are red. This makes it very easy to find tasks that still need work as well as measure the overall status of a project. Sometimes, a large task list can feel very intimidating. That is why I added the ability to hide completed tasks with the check of a box. Matt wanted to take this one step farther; he wanted the ability to also hide tasks with a closed bug. This is why you will find 2 checkboxes at the top of the dashboard that allow you to custimize which tasks are visible. Eventually, I might add support for specifying this in the URL to allow groups to link to a particular view of the dashboard. In order to make it as easy as possible for new contributors to get involved with DEX projects, I wanted to have a way to document what a project is about and how to handle tasks. I decided to use the wiki for this. All of the per-project documentation lives at http://wiki.debian.org/DEX//
. You can even take advantage of wiki markup to format the documentation. The script will parse the HTML files generated by the wiki, do some minor cleanup, and then display the documentation at the top of the page. My original plan was to use the ?action=raw output, but the lack of formatting proved too restrictive. My second plan was to try and use something like BeautifulSoup or a regex to filter non-whitelisted tags out of the wiki-generated html. This failed and proved to be unnecessary. The wiki does a pretty decent job of preventing malicious markup from ending up on the dashboard. There is a second graph that is displayed on the dashboard. This graph shows the number of tasks each person has completed. The graph is sorted so that the tallest bars on the left, and the goal is to provide some immediate recognition of work done by contributors. Since we essentially allow anyone to go ahead and modify the dashboard, we knew it was important to have a method in place for dealing with abuse. Any malicious edits made on the wiki can easily be reverted. This idea of reverting to an earlier revision is what inspired me to use a second local git repository to store the projects/ directory. This directory stores all of the changes made via the web interface. Whenever the form is submitted or the script runs to update the list of tasks, any changes made to the projects/ directory are committed. This means that if a malicious user decides to delete everything on the dashboard, we can quickly and easily revert the changes. The revision history might also be interesting to analyze at a future date. When multiple people are collaborating on a project, an issue tracker can be quite useful. For some reason, we did not set one up until quite late into the project. Despite that, we are still using it to track known bugs and feature requests. The issue tracker will become even more useful once the dashboard starts to be utilized by more people. I spent a fair bit of time working on having the dashboard immediately respond to changes. For example, if you change the status of a task, the row color will instantly update. The form will also be submitted in the background, eliminating the need to hit submit to save the change. I also use ajax in some new dialogs that allow the user to create new projects and/or tasks via the web. While these forms are submitted in the background via ajax, I am unable to have the changes show up on the dashboard immediately. The generation of the task list is a bit slow, so having the script run more often is not really a good idea. The next step for the dashboard is to really open it up for testing. We hope to start up a new DEX project shortly. This will allow us to see which features work and which need fixing. It will also help us find some of the bugs that are probably hiding in the code. Finally, if you are interested in helping out with DEX or dextools, my code is available in a git repository (http://anonscm.debian.org/gitweb/?p=dex/gsoc2011.git) on alioth. There is also the issue tracker (https://alioth.debian.org/tracker/index.php?group_id=100600&atid=413120) where you can report bugs and request new features. Finally, you can join the debian-derivatives mailing list, join #debian-derivatives on OFTC, or contact me directly via email or on IRC (nhandler). I have really enjoyed working on dextools this summer. I would like to thank Matt Zimmerman, Stefano Zacchiroli, and everyone else who helped with the project. I look forward to working with all of you more in the future.

Vincent Bernat: SSL termination: stunnel, nginx & stud

Here is the short version: to get better performance on your SSL terminator, use stud on 64bit system with patch from meric Brun for SSL session reuse with some AES cipher suite (128 or 256, does not really matter), without DHE, on as many cores as needed, a key size of 1024 bits unless more is needed.

Introduction A quick note: when I say SSL, you should read TLS v1 instead. Look at the article for TLS on Wikipedia for some background on this. One year ago, Adam Langley, from Google, stated SSL was not computationally expensive any more:
In January this year (2010), Gmail switched to using HTTPS for everything by default. Previously it had been introduced as an option, but now all of our users use HTTPS to secure their email between their browsers and Google, all the time. In order to do this we had to deploy no additional machines and no special hardware. On our production frontend machines, SSL/TLS accounts for less than 1% of the CPU load, less than 10KB of memory per connection and less than 2% of network overhead. Many people believe that SSL takes a lot of CPU time and we hope the above numbers (public for the first time) will help to dispel that. If you stop reading now you only need to remember one thing: SSL/TLS is not computationally expensive any more.
This is a very informative post containing tips on how to enhance SSL performance by reducing latency. However, unlike Gmail, you may still be worried by SSL raw performances. Maybe each of your frontends is able to serve 2000 requests per second and CPU overhead for SSL is therefore significative. Maybe you want to terminate SSL in your load balancer (even if you know this is not the best way to scale).

Tuning SSL There are a lot of knobs you can use to get better performances from SSL: choosing the best implementation, using more CPU cores, switching to 64bit system, choosing the right cipher suite and the appropriate key size and enabling a session cache. We will consider three SSL terminators. They all use OpenSSL behind the hood. stunnel is the oldest one and uses a threaded model. stud is a recent attempt to write a simple SSL terminator which is efficient and scalable. It uses the one-process-per-core model. nginx is a web server and it can be used as reverse proxy and therefore act as SSL terminator. It is known to be one of the most efficient web server, hence the choice here. It also features built-in basic load balancing. Since stud and stunnel does not have this feature, we use them with HAProxy, an high performance load-balancer that usually defers the SSL part to stunnel (but stud can act as a drop-in replacement here). Those implementations were already tested by Matt Stancliff. He first concluded nginx sucked at SSL then that nginx did not suck at SSL (in the first case, nginx was the only one to select a DHE cipher suite). The details were very scarce. I hope to bring here more details. This brings the importance of the selected cipher suite. The client and the server must agree on the cipher suite to use for symmetric encryption. The server will select the strongest one it supports from the list proposed by the client. If you enable some expensive cipher suite on your server, it is likely to be selected. The last important knob is SSL session reuse. It matters for both performance and latency. During the first handshake, the server will send a session ID. The client can use this session ID to request an abbreviated handshake. This handshake is shorter (latency improvement by one round-trip) and allows to reuse the previously negociated master secret (performance improvement by skipping the costliest part of the handshake). See the article from Adam Langley for additional information (with helpful drawings). The following table shows what cipher suite is selected by some major web sites. I have also indicated wheter they support session reuse. See this post from Matt Palmer to know how to check this.
Site Cipher Session reuse?
www.google.com RC4-SHA
www.facebook.com RC4-MD5
twitter.com AES256-SHA
windowsupdate.microsoft.com RC4-MD5
www.paypal.com AES256-SHA
www.cmcicpaiement.fr DHE-RSA-AES256-SHA
RFC 5077 defines another mechanism for session resumption that does not require any server-side state. I did not investigate much how this works but it does not rely on the session ID.

Benchmarks All those benchmarks have been run on a HP DL 380 G7, with two Xeon L5630 (running at 2.13GHz for a total of 8 cores), without hyperthreading, using a 2.6.39 kernel (HZ is set to 250) and two Intel 82576 NIC. Linux conntrack subsystem has been disabled and file limits have been raised over 100,000. A Spirent Avalanche 2900 appliance is used to run the benchmarks. We are interested in raw SSL performances in term of handshakes per second. Because we want to observe the effects of session reuse, the scenario runs by most tests lets clients doing four successive requests and reusing the SSL session for three of them. There is no HTTP keepalive. There is no compression. The size of the HTTP answer from the server is 1024 bytes. Those choices are done because our primary target is the number of SSL handshakes per second. It should also be noted that HAProxy alone is able to handle 22,000 TPS on one core. During the tests, it was never the bottleneck.

Implementation We run a first bench to compare nginx, stud and stunnel on one core. This bench runs on a 32bit system, with AES128-SHA1 cipher suite and a 1024bit key size. Here is the result for stud (version 0.1, with meric Brun s patch for SSL session reuse): stud, 1 CPU The most important plot is the top one. The blue line is the attempted number of transactions per second (TPS) while the green one is the successful number of TPS. When the two lines start to diverge, this means we reach some kind of maximum: the number of unsuccessful TPS also starts to raise (the red line). There are several noticeable points: the maximum TPS (788 TPS), the maximum TPS with an average response time less than 100 ms (766 TPS), less than 500 ms (776 TPS) and the maximum TPS with less than 0.01% of packet loss (783 TPS). Let s have a look at nginx (version 1.0.5): nginx, 1 CPU It is able to get the same performance as stud (763 TPS). However, over 512 TPS, you get more than 100 ms of response time. Over 556 TPS, you even get more than 500 ms! I get this behaviour in every bench with nginx (with or without proxy_buffering, with or without tcp_nopush, with or without tcp_nodelay) and I am unable to explain it. Maybe there is something wrong in the configuration. After hitting this limit, nginx starts to process connections by bursts. Therefore, the number of successful TPS is plotted using a dotted line while the moving average over 20 seconds is plotted with a solid line. On the next plot, you can see the compared performance of the three implementations. On this kind of plot, the number of TPS that we keep is the maximum number of TPS where loss is less than 0.1% and average response time is less than 100 ms. stud achieves a performance of 766 TPS while nginx and stunnel are just above 500 TPS. stunnel vs stud vs nginx, 1 CPU

Number of cores With multiple cores, we can affect several of them to do SSL hard work. To get better performance, we pin each processes to a dedicated CPU. Here is the repartition used during the tests:
1 core 2 cores 4 cores 6 cores
CPU 1, Core 1 network network network network + haproxy
CPU 1, Core 2 haproxy haproxy haproxy SSL
CPU 1, Core 3 SSL SSL SSL SSL
CPU 1, Core 4 - SSL SSL SSL
CPU 2, Core 5 - - network SSL
CPU 2, Core 6 - - SSL SSL
CPU 2, Core 7 - - SSL SSL
CPU 2, Core 8 system system system system + haproxy
Remember, we have two CPU, 4 cores on each CPU. Cores on the same CPU share the same L2 cache (on this model). Therefore, the arrangement inside a CPU is not really important. When possible, we try to keep things together on the same CPU. The SSL processes always get exclusive use of a core since they will always be the most busy. The repartition is done with cpuset(7) for userland processes and by setting smp_affinity for network card interrupts. We keep one core for the system. It is quite important to be able to connect and monitor the system correctly even when it is loaded. With so many cores, we can afford to reserve one core for this usage. Beware! There is a trap when pining processes or IRQ to a core. You need to check /proc/cpuinfo to discover the mapping between kernel processors and physical cores. Sometimes, second kernel processor can be the first core of the second physical processor (instead of the second core of the first physical processor). stunnel vs stud vs nginx, 6 CPU As you can see in the plot above, only stud is able to scale properly. stunnel is not able to take advantage of the cores and its performances are worse than with a single core. I think this may be due to its threaded model and the fact that the userland for this 32bit system is a bit old. nginx is able to achieve the same TPS than stud but is disqualified because of the increased latency. We won t use stunnel in the remaining tests.

32bit vs 64bit The easiest way to achieve a performance boost is to switch to a 64bit system. TPS are doubled. On our 64bit system, thanks to the use of a version of OpenSSL with the appropriate support, AES-NI, a CPU extension to improve the speed of AES encryption/decryption, is enabled. Remaining tests are done with a 64bit system. stud vs nginx, 64bit

Ciphers and key sizes In our tests, the influence of ciphers is minimal. There is almost no difference between AES256 and AES128. Using RC4 adds some latency. The use of AES-NI may have helped to avoid this latency for AES. On the other hand, using a 2048bit key size has a huge performance hit. TPS are divided by 5. stud: cipher suites and key sizes

Session cache The last thing to check is the influence of SSL session reuse. Since we are on a local network, we see only one of the positive effects of session reuse: better TPS because of reduced CPU usages. If there was a latency penalty, we should also have seen better TPS thanks to the removed round-trip. stud: session reuse This plot also explains why stud performances fall after the maximum: because of the failed transactions, the session cache is not as efficient. This phenomenon does not exist when session reuse is not enabled.

Conclusion Here is a summary of the maximum TPS reached during the benchmark (with an average response time below 100ms). Our control use case is the following: 64bit, 6 cores, AES128, SHA1, 1024bit key, 4 requests into the same SSL session.
Context nginx 1.0.5 stunnel 4.41 stud 0.1 (patched)
1 core, 32bit 512 TPS 503 TPS 766 TPS
2 cores, 32bit 599 TPS - -
32bit 804 TPS 501 TPS 4251 TPS
- 1799 TPS - 9000 TPS
AES256 - - 8880 TPS
RC4-MD5 - - 7370 TPS
2048bit - - 1643 TPS
no session reuse - - 5844 TPS
80 requests per SSL session - - 10797 TPS
Therefore, stud in our control scenario is able to sustain 1500 TPS per core. It seems to be the best current option for a SSL termination. It is not available in Debian yet, but I intend to package it. Here is how stud is invoked:
# ulimit -n 100000
# stud  -n 2 -f 172.31.200.15,443 -b 127.0.0.1,80 -c ALL \
>   -B 1000 -C 20000 --write-proxy \
>   =(cat server1024.crt server1024.key dhe1024)
You may also want to look at HAProxy configuration, nginx configuration and stunnel configuration.

Rudy Godoy: Compute clusters for Debian development and building final report

Compute clusters for Debian development and building final report Summary
-
The goal of this project was intended to have Eucalyptus cloud to
support ARM images so it allows Debian developers and users to be able
to use such facility for taks such package building, software
development (ie. Android) under a Debian pre-set image,
software testing many others. What was expected to have at the end is a modified version of Eucalyptus
Cloud that supports ARM images on the first place. To date this goal has
been reached but is not complete, read production-ready. Extensive test
needs to be done. Besides that we have another goal which is to get
Debian community to use this new extended tool. Project overview
-
Eucalyptus is a hybrid cloud computing platform which has a Open Source
(FLOSS) version. It s targetted to be used for PaaS (Platform as a
Service), IaaS (Infrastructure as a Service) and other distribution
models. It can be used also for cloud management. Given that it has
implemented the EC2, for computing, and the S3, for storage, API, it s
compatible with existing public clouds such Amazon EC2. Currently it
supports running i386 and amd64 images or NC (Node Controllers) in
Eucalyptus naming. Eucalyptus is a complex piece of software. It s architechture it s
modular composed by five components. Cloud Controller (CLC), Walrus (W),
Storage Controller (SC), Cluster Controller (CC) and Node Controller
(NC). The first three are written in Java and the remaining are written
in C. Our project modifications was targetted to the NC component,
altough there is a remaining task for hacking the UI to allow setting
the arch of the uploaded NC image instance. The Node Controller is in charge of setting the proper information for
Eucalyptus to be able to run virtualized images. Eucalyptus uses XEN and
KVM hyphervisor to handle internal virtualization subsystem, and
Libvirt, which is an abstraction of the existing virtualization
libraries, for program interfacing. Having that in mind we are back to our project. For our project to be
sucessful we had various tasks to do. Beginning with understanding such
complex piece of software, followed by hacking the requiered bits and
later integrate the work so it results in a useful tool. Our approach to
the project was then inline with such description. The project s history
I started my participation in GSoC approaching Steffen to discuss about
what was expected, or more accurately, what was in his mind. We
exchanged emails previous to my application and that resulted on my
application being submitted. From the beginning I should tell that I
wasn t much clear on the final product of the project, however we
refined ideas and goals during the weeks following to the official
begining of the project. What was clear for me, after all, is that for
this to see the light and gain adoption Eucalyptus code needed to be
dealt with. Our first task was review ARM image creation from scratch, using the
work done by Aurelien and Dominique in previous GSoC. I ve managed to
get an updated ARM image running under qemu-system-arm. The issues
presented in the past were almost unexistant now that the versatile
kernel is official. You can see this on my first report. After that being done and sometimes in parallel my main goal was then understand
the internals of the Eucalyptus software in order to figure out it s
feasibility, where do we need to extend and how big the task is, we
didn t knew upfront. From the beginning of the project Steffen was kind
to introduce me to the Eucalyptus developers and that have resulted in a
good outcome for Debian, IMHO, to date. Understanding Eucalyptus internals was quite a fun task to say the less. As you
can see on the first part of the report Eucalyptus is modularized and
the component I was expected to work with was the NC (Node
Controller). Given that I isolated my work focus, I started to focus on
learning the internals about that component. Node Controller as described is in charge of talking with
virtualization hyphervisors in order to arrange things to run guest
image instances. The module has basically one main component: handler.c,
in charge to talk to the appropiate hyphervisor and there are
extensions (think of OOP polymorphism but acknoledge it s plain C)
that interact with KVM or XEN. I figured that if qemu-kvm is ran in Hyphervisor mode we can manage to
run an ARM image with qemu-system-arm. Given that Eucalyptus has
interaction with KVM hyphervisor in place, this answered the question of
the project s feasibility. First green light on.
>From this point the scope reduced to interacting with the KVM handler
(node/handler_kvm.c) and extend it to support running an image that is
not amd64 or i386. NC makes use of libvirt to abstract interaction with Hyphervisors. So,
the next phase was learning about it s API and figure what s needed to
be modified next. Libvirt uses a XML file for setting Domain (in
libvirt s naming) definitions. So, Eucalyptus provides a Perl wrapper to
generate this file on runtime and allow the NC to invoke libvirt s API
to run the instance. Next task then, was adapt such script to support
ARM arch. The current script is taiolred for amd64 and i383. I worked on
that front and managed to get a script prototype, that can later be
improved and support more arch s. Generating an adequate Libvirt s XML Domain definition file for ARM can
be a heroic task. There are many things to have in mind given the
diversity of the ARM processor and vendors. I focused on the versatile
flavour given that I was going to test the image I built on the first
place and it ran fine under qemu-system-arm.
The Perl script wrapper then was adapted for such configuration and it
can be tested independently by issuing the following command: $ tools/gen_kvm_libvirt_xml arch arm The arch parameter is what I implemented and it s intended to be
called from the kvm handler on instance creation. With the extensibility
in mind I ve created a hash to associate the arch with their
corresponding emulator. our %arches = (
amd64 => /usr/bin/kvm ,
arm => /usr/bin/qemu-system-arm ,
); Added the arch parameter to the GetOptions() function and used
conditions to tell whether the user is looking for a particular arch,
arm in our case. The most important parts to be considered are the
, and entries. hvm $local_kvm There s also and that require to be tailored for arm. root=0800 As output the script generates an XML template that can be adapted to
your needs and it could be used and tested with tools like Libvirt s
virsh. So that, it can be useful independently of Eucalyptus. I managed
to get to this point before the midterm evaluation. Now that we had the XML wrapper almost done, the next task was to make
the handler call pass the arch as an argument to the script, so the
image is loaded with the proper settings and we are able to run it. Eucalyptus doesn t have a arch field for NC s instances. So, after approaching
Eucalyptus developers, with whom we had already being interacting, I
settled to my proposal of extending the ncInstance struct with an arch
field (util/data.h). The ncInstance_t struct stores the metadata for the
instance being created. It s used for storing runtime data as well as
network configuration and more. It was indeed the right place to add a
new field. I did so by creating the archId field.
Now I needed to make sure the arch information is stored and later used on the
libvirt s call. typedef struct ncInstance_t
char instanceId[CHAR_BUFFER_SIZE];
char imageId[CHAR_BUFFER_SIZE];
char imageURL[CHAR_BUFFER_SIZE];
char kernelId[CHAR_BUFFER_SIZE];
char kernelURL[CHAR_BUFFER_SIZE];
char ramdiskId[CHAR_BUFFER_SIZE];
char ramdiskURL[CHAR_BUFFER_SIZE];
char reservationId[CHAR_BUFFER_SIZE];
char userId[CHAR_BUFFER_SIZE];
char archId[CHAR_BUFFER_SIZE];
int retries; /* state as reported to CC & CLC */
char stateName[CHAR_BUFFER_SIZE]; /* as string */
int stateCode; /* as int */ /* state as NC thinks of it */
instance_states state; char keyName[CHAR_BUFFER_SIZE*4];
char privateDnsName[CHAR_BUFFER_SIZE];
char dnsName[CHAR_BUFFER_SIZE];
int launchTime; // timestamp of RunInstances request arrival
int bootTime; // timestamp of STAGING->BOOTING transition
int terminationTime; // timestamp of when resources are released (->TEARDOWN transition) virtualMachine params;
netConfig ncnet;
pthread_t tcb; /* passed into NC via runInstances for safekeeping */
char userData[CHAR_BUFFER_SIZE*10];
char launchIndex[CHAR_BUFFER_SIZE];
char groupNames[EUCA_MAX_GROUPS][CHAR_BUFFER_SIZE];
int groupNamesSize; /* updated by NC upon Attach/DetachVolume */
ncVolume volumes[EUCA_MAX_VOLUMES];
int volumesSize;
ncInstance; With that in place what was left was modifying the functions that
store/update the ncInstance data, and also the libvirt s function that
calls the gen_kvm_libvirt_xml script. I ve modified the following files:
- util/data.c
- node/handlers_kvm.c
- node/handlers. c,h
- node/test.c
- node/client-marshall-adb.c Most important the allocate_instance() function that is in charge of setting up
the instance metadata a prepare it to pass it to the handler, then
hyphervisor trough Libvirt s API. The function now has a new archId
parameter as well, to keep coherence with the field name. It also
handles whether the field is set or not. We (Eucalyptus developers and
I) haven t settled wether to initialize this field with a default value
or not. I d stepped up and initialized with a NULL value for this string
type var. if (archId != NULL)
strncpy(inst->archId, archId, CHAR_BUFFER_SIZE);
Stores the value only if it s passed to the function. This is essential to
don t break existing functionality and keep consistency for later releases.
With this we almost finished the part of extending Eucalyptus to support
arm images. It took quite long to get to that point. Next step: test. As I mentioned in my previous report the current Eucalyptus packaging
has issues. From the beginning I ve approached the pkg-eucalyptus team,
who were very hepful. So I myself set me up and joined the pkg team with
commit access to the repo. Even the GSoC is not intended for packaging
labour, I needed to clear things on that side because what we want is
adoption so anyone, say a DSA or a user, could setup a cloud that has
support for running arm instances under amd64 arch. Over the weeks between mid-term evaluation and past week I ve worked on
that front. Results were good, as you can see in the pkg-eucalyptus
mailing list and SVN repo.
Eucalyptus has a couple of issues that because of it s nature and complexity
triggered build errors. Those issues came from the Java side of the project and
few form the C-side. The C-part was a problem with AXIS2 Jar used to generate
stubs for later inclusion on build-time. There s no definitive solution to date
because one of the Makefile on gatherlog/Makefile issues a subshell call that
doesn t catches the AXIS_HOME environment variable. I ve worked around this
by defining it as a session env var from .zshrc. The other problem is related
to the Java libary versioning and most likely (we had to investigate further)
to groovy versioning. As I explained Eucalyptus has 3 components written in Java. The Java code uses
extensively the AXIS2 library for implementing webservices calls, the groovy
language for JVM, and many other Java libaries. Eucalyptus open source version
ships both online and offline versions. The difference is basically that
the offline version ships the Java libaries JAR files inside the source code,
so you can build with all required deps. Our former packaging used a file to list which Java libraries the package
depends on and it symlinked them using system wide installed packages. This
rather than helping out triggered a lot of problems I explaing with more detail
on the pkg-eucalyptus ml. I worked around this by telling the debian/rules
not to use such file to symlink and instead use the existing ones from
the source. The last weekend I managed to get to that point and built
sucessfully the software under Debian. I ve done that in order to have a
complete build-cycle for my changes, and then test. In fact today I ve
spotted and fixed a couple of bugs there. What s available now

To date we have a Eucalyptus branch where my patches are sent. The level of
extension is nearly complete, more testing needed. One missing bit is to
change the UI so that the user selects which arch her image is and that
value is passed to the corresponding functions on the Node Controller
component. We also have an ARM image that can be tested and later automated. I ve
recently learned about David Went s VMBuilder repo that extends Ubuntu s
vmbuilder to support image creationg. I might talk to him to adapt the tool
in order to support creation of arm images and use it to upload to an
Eucalyptus cloud. I ve also created a wiki page with different bits on which I was working on.
I ve yet need to craft it to be more educational. I guess I m going to use
this report as a source :) We also had more strong cooperation with the Eucalyptus project and
involved their developers on the packaging and this project, which is
something I consider a great outcome for this project and GSoC goals:
to attract more people to contribute to FLOSS. I ve also been contacted by
people from the Panda Project and we might cooperate also. Future work

I plan to keep working on the project regardless the GSoC ends. Our goal
as Debian could be integrating this into the Eucalyptus upstream
branch. We have good relations with them so expect news from that side.
I also plan to keep working with the Eucalyptus team and related
software in Debian, given that I m familiarized with the tools and
projects.
I m also planning to advocate SoC for Debian in my faculty. To date we
had already 4 students, IIRC, that have participated in the past. Project challenges and lessons
During the project I faced many challenges both in the personal side
and in the technical one. This part is a bit personal but I expect we
learn from this. First challenge was the where do I sit problem. My project was
particular, indeed quite different from the others on it s nature. I had
to work on a software that is not Debian s and then come and say Hey we
have this nice tool for you, come test it! . So, indeed, my focus was on
the understanding of such tool, Eucalyptus, and not much on looking back
at Debian because I didn t feel I had something to advertise yet and
indeed I got most valuable/useful feedback from Eucalyptus developers
rather than Debian s, which for the case is OK IMHO. I had great
mentoring. This situation probably looked a bit of isolation from my
side, from Debian s POV, but it was not intended it s just how it needed
to be IMHO. I felt that I wasn t contributing directly to the
project. I ve spoke about such thing with Steffen a couple of times. I d
like to say that it was also my concern but I probably failed on
communicating this, second challenge. Third challenge was more technical and related to the first one. Since I
was not writing any code for a Debian native package/program but instead for
other project I faced the situation of where to publish my
contributions. Eucalyptus had some issues on managing their FLOSS repo
and the current development one is outdated comparing to the
-src-offline 2.0.3 release. The project didn t fit pkg-eucalyptus repo
neither, even we thought to branch the existing trunk and ship my
contribs as quilt patches, but it involved a lot of more work and burn
on reworking something that has issues now. Later on time I branched the
bzr eucalyptus-devel Launchpad repo and synced there with the
src-offline code. I was slow to react on thing I can say. Fourth challenge was also technical and still dealing with. I was looking to
setup a machine to set a cloud and test my branch. The Dean of my faculty
kindly offered a machine but I ve never managed to get things arranged
with the technical team. Steffen and I discussed about this and evaluated
options, at the end we settled on pushing adoption rather than showcasing it.
Since for adoption we need a use case, I ve spend some SoC money on hardware
for doing this. I should have news this week on that side :) Finally, I d like to thank everyone on the Debian SoC team for this
opportunity to participate. I like to thank Steffen for his effort on
arranging things for me, Graziano from Eucalyptus for his advice on
working with the software code. The different people from Eucalyptus I
interacted with and showed interest on the project s sucess. My
classmates and teachers from the Computer Science School at UCSP in
Arequipa-Peru, friends from the computing community in Peru SPC and
finally my family. Thank you, I learned a lot, specially on the personal
side. As Randy Pausch put: The brick walls are there to give us a
chance to show how badly we want something. Resources
Please see the Wiki page[1] for any reference to the project s resources. 1- http://wiki.debian.org/SummerOfCode2011/BuildWithEucalyptus/ProjectLog Best regards,
Rudy

19 August 2011

Kai Wasserb ch: wine-unstable: partly broken on amd64

Just a short entry, as I've already got a few e-mails about this: the JPEG is broken at the moment for my unofficial wine-unstable packages on amd64. This is due to #638543 in ia32-libs-dev. Please see the bug report for a detailed explanation. A rebuild with libjpeg62-dev isn't an option, as other build dependencies pull libjpeg8-dev in anyway. Thus forcing the older version on amd64 just generates a FTBFS. Full multi-arch support in the toolchain (including dpkg) or an update for ia32-libs are the two viable solutions for this as far as I can tell.

18 August 2011

Thorsten Glaser: How not to create DEB files

Once upon a time, there was Deb and Ian. That was about exactly 18 years ago. We don t talk about the 0.939000 format any more, but they eventually settled on:

	$ ar rc pkg_1.0_all.deb debian-binary control.tar.gz data.tar.gz
	$ hexdump -C pkg_1.0_all.deb   head
	00000000  21 3c 61 72 63 68 3e 0a  64 65 62 69 61 6e 2d 62   !<arch>.debian-b 
	00000010  69 6e 61 72 79 20 20 20  31 33 31 33 36 38 33 35   inary   13136835 
	00000020  32 39 20 20 31 30 30 36  20 20 32 30 30 20 20 20   29  1006  200    
	00000030  31 30 30 36 34 34 20 20  34 20 20 20 20 20 20 20   100644  4        
	00000040  20 20 60 0a 32 2e 30 0a  63 6f 6e 74 72 6f 6c 2e      .2.0.control. 
	00000050  74 61 72 2e 67 7a 20 20  31 33 31 33 36 38 33 35   tar.gz  13136835 
	00000060  32 39 20 20 31 30 30 36  20 20 32 30 30 20 20 20   29  1006  200    
	00000070  31 30 30 36 34 34 20 20  31 33 39 31 20 20 20 20   100644  1391     
	00000080  20 20 60 0a 1f 8b 08 00  00 00 00 00 00 03 ed 59      ............Y 
	00000090  eb 6f db 36 10 f7 d7 f0  af b8 3a 5e 9b 74 b1 f5   .o.6......:^.t.. 
 

By then, systems were a.out(5), and everything was good. (Of course, if you look at the mtimes, you ll notice I faked this. But it s really equivalent to the real thing.

But oh horror! GNU binutils, not always everyone s friend, switched from using BSD style Unix Archiver libraries in ar(1) to SYSV style libraries on elf(5) systems:

	$ ar rc on-elf debian-binary control.tar.gz data.tar.gz
	$ hexdump -C on-elf   head
	00000000  21 3c 61 72 63 68 3e 0a  64 65 62 69 61 6e 2d 62   !<arch>.debian-b 
	00000010  69 6e 61 72 79 2f 20 20  31 33 31 33 36 38 33 35   inary/  13136835 
	00000020  32 39 20 20 31 30 30 36  20 20 32 30 30 20 20 20   29  1006  200    
	00000030  31 30 30 36 34 34 20 20  34 20 20 20 20 20 20 20   100644  4        
	00000040  20 20 60 0a 32 2e 30 0a  63 6f 6e 74 72 6f 6c 2e      .2.0.control. 
	00000050  74 61 72 2e 67 7a 2f 20  31 33 31 33 36 38 33 35   tar.gz/ 13136835 
	00000060  32 39 20 20 31 30 30 36  20 20 32 30 30 20 20 20   29  1006  200    
	00000070  31 30 30 36 34 34 20 20  31 33 39 31 20 20 20 20   100644  1391     
	00000080  20 20 60 0a 1f 8b 08 00  00 00 00 00 00 03 ed 59      ............Y 
	00000090  eb 6f db 36 10 f7 d7 f0  af b8 3a 5e 9b 74 b1 f5   .o.6......:^.t.. 
 

Can you spot the difference?

Of course, ELF is what you want , so there is little choice. Unix Archiver libraries are system dependent, and no format has ever been normed, but DEB files use it as format so what is one to do?

	$ GNUTARGET=a.out-i386-linux ar rc with-aout \
	> debian-binary control.tar.gz data.tar.gz
	$ md5sum pkg_1.0_all.deb with-aout on-elf
	248f78d42f8ca8f2a3560f9800b2bf01  pkg_1.0_all.deb
	248f78d42f8ca8f2a3560f9800b2bf01  with-aout
	09eca70c9b11b6b55bbadcab5c3201fb  on-elf
 

OK, and what do I do on my Debian/m68k system?

ar(1) uses bfd, and GNU binutils can not only forcibly set the target emulation but also show them:

debian_m68k$ ar -h 2>&1 grep '^ar: supported targets'
ar: supported targets: elf32-m68k a.out-m68k-linux elf32-little elf32-big plugin srec symbolsrec verilog tekhex binary ihex trad-core
debian_i386$ ar -h 2>&1 grep '^ar: supported targets'
ar: supported targets: elf32-i386 a.out-i386-linux pei-i386 elf32-little elf32-big elf64-x86-64 elf32-x86-64 pei-x86-64 elf64-l1om elf64-k1om elf64-little elf64-big plugin srec symbolsrec verilog tekhex binary ihex trad-core
debian_i386$ ar -h 2>&1 grep '^ar: supported targets' # binutils-multiarch
ar: supported targets: elf32-i386 a.out-i386-linux pei-i386 elf32-little elf32-big elf64-alpha ecoff-littlealpha elf64-little elf64-big elf32-littlearm elf32-bigarm elf32-hppa-linux elf32-hppa elf64-x86-64 elf32-x86-64 elf64-l1om elf64-k1om elf64-ia64-little elf64-ia64-big pei-ia64 elf32-m68k a.out-m68k-linux coff-m68k versados ieee a.out-zero-big elf32-tradbigmips elf32-tradlittlemips ecoff-bigmips ecoff-littlemips elf32-ntradbigmips elf64-tradbigmips elf32-ntradlittlemips elf64-tradlittlemips elf32-powerpc aixcoff-rs6000 elf32-powerpcle ppcboot elf64-powerpc elf64-powerpcle aixcoff64-rs6000 aix5coff64-rs6000 elf32-s390 elf64-s390 elf32-shbig-linux elf32-sh-linux elf32-sh64-linux elf32-sh64big-linux elf64-sh64-linux elf64-sh64big-linux elf32-sparc a.out-sparc-linux elf64-sparc a.out-sunos-big pei-x86-64 elf32-m32r-linux elf32-m32rle-linux elf32-spu plugin srec symbolsrec verilog tekhex binary ihex trad-core
mirbsd_i386$ ar -h 2>&1 grep '^ar: supported targets'
ar: supported targets: elf32-i386 coff-a29k-big a.out.adobe aix5coff64-rs6000 a.out-zero-big a.out-mips-little epoc-pe-arm-big epoc-pe-arm-little epoc-pei-arm-big epoc-pei-arm-little coff-arm-big coff-arm-little a.out-arm-netbsd pe-arm-big pe-arm-little pei-arm-big pei-arm-little b.out.big b.out.little efi-app-ia32 efi-app-ia64 elf32-avr elf32-big elf32-bigarc elf32-bigarm elf32-bigarm-symbian elf32-bigarm-vxworks elf32-bigmips elf32-cr16c elf32-cris elf32-crx elf32-d10v elf32-d30v elf32-dlx elf32-fr30 elf32-frv elf32-frvfdpic elf32-h8300 elf32-hppa-linux elf32-hppa-netbsd elf32-hppa elf32-i370 elf32-i386-freebsd elf32-i386-vxworks elf32-i860-little elf32-i860 elf32-i960 elf32-ia64-hpux-big elf32-ip2k elf32-iq2000 elf32-little elf32-littlearc elf32-littlearm elf32-littlearm-symbian elf32-littlearm-vxworks elf32-littlemips elf32-m32r elf32-m32rle elf32-m32r-linux elf32-m32rle-linux elf32-m68hc11 elf32-m68hc12 elf32-m68k elf32-m88k elf32-mcore-big elf32-mcore-little elf32-mn10200 elf32-mn10300 elf32-msp430 elf32-nbigmips elf32-nlittlemips elf32-ntradbigmips elf32-ntradlittlemips elf32-openrisc elf32-or32 elf32-pj elf32-pjl elf32-powerpc elf32-powerpc-vxworks elf32-powerpcle elf32-s390 elf32-sh elf32-shbig-linux elf32-shl elf32-shl-symbian elf32-sh-linux elf32-shl-nbsd elf32-sh-nbsd elf32-sh64 elf32-sh64l elf32-sh64l-nbsd elf32-sh64-nbsd elf32-sh64-linux elf32-sh64big-linux elf32-sparc elf32-tradbigmips elf32-tradlittlemips elf32-us-cris elf32-v850 elf32-vax elf32-xstormy16 elf32-xtensa-be elf32-xtensa-le elf64-alpha-freebsd elf64-alpha elf64-big elf64-bigmips elf64-hppa-linux elf64-hppa elf64-ia64-big elf64-ia64-hpux-big elf64-ia64-little elf64-little elf64-littlemips elf64-mmix elf64-powerpc elf64-powerpcle elf64-s390 elf64-sh64 elf64-sh64l elf64-sh64l-nbsd elf64-sh64-nbsd elf64-sh64-linux elf64-sh64big-linux elf64-sparc elf64-tradbigmips elf64-tradlittlemips elf64-x86-64 mmo pe-powerpc pei-powerpc pe-powerpcle pei-powerpcle a.out-cris demo64 ecoff-bigmips ecoff-biglittlemips ecoff-littlemips ecoff-littlealpha coff-go32 coff-go32-exe coff-h8300 coff-h8500 a.out-hp300hpux a.out-i386 a.out-i386-bsd coff-i386 a.out-i386-freebsd a.out-i386-lynx coff-i386-lynx msdos a.out-i386-netbsd i386os9k pe-i386 pei-i386 coff-i860 coff-Intel-big coff-Intel-little ieee coff-m68k coff-m68k-un a.out-m68k-lynx coff-m68k-lynx a.out-m68k-netbsd coff-m68k-sysv coff-m88kbcs a.out-m88k-mach3 a.out-m88k-openbsd mach-o-be mach-o-le mach-o-fat coff-maxq pe-mcore-big pe-mcore-little pei-mcore-big pei-mcore-little pe-mips pei-mips a.out-newsos3 nlm32-alpha nlm32-i386 nlm32-powerpc nlm32-sparc coff-or32-big a.out-pc532-mach a.out-ns32k-netbsd a.out-pdp11 pef pef-xlib ppcboot aixcoff64-rs6000 aixcoff-rs6000 coff-sh-small coff-sh coff-shl-small coff-shl pe-shl pei-shl coff-sparc a.out-sparc-little a.out-sparc-linux a.out-sparc-lynx coff-sparc-lynx a.out-sparc-netbsd a.out-sunos-big sym a.out-tic30 coff-tic30 coff0-beh-c54x coff0-c54x coff1-beh-c54x coff1-c54x coff2-beh-c54x coff2-c54x coff-tic80 a.out-vax-bsd a.out-vax-netbsd a.out-vax1k-netbsd versados vms-alpha vms-vax coff-w65 coff-we32k coff-z8k elf32-am33lin elf32-ms1 srec symbolsrec tekhex binary ihex netbsd-core

Wow. While binutils share no single supported working target, they can be built multiarch, or (on MirBSD) with --enable-targets=all --enable-64-bit-bfd. Doesn t help if you want to stay portable: GNUTARGET=srec is common on all Debian (sid) binutils versions (single or multiarch), but errors out on older binutils. The a.out-* targets are not common. Sure, you could hack around things, but this is tedious. If you follow things or know me a little, you might already have guessed that I wouldn t let that stand.

pax(1) to the rescue. On MirBSD, we use paxtar, which has cpio(1) and tar(1) front-ends and supports multiple formats (4 cpio and 2 tar variants) and has already been extended a lot and is lovingly called paxmirabilis (mirabilos peace in Latin) it has options to anonymise archives: set uid and gid to zero, set mtime to zero, (for ustar) only write the numeric uid and gid to the archive, (for cpio formats) serialise inodes and device information, write content of hardlinked files only once (breaks partial extraction but saves a lot of space, e.g. 2 MiB off the Grml initrd.gz). And, recently, the ability to append a trailing slash to pathnames of ustar members which are directories (GNU tar does it and I thought some Debian utilities check for it). So why not (the -M dist and fakeroot set the uid/gid to 0)

	$ find debian-binary control.tar.gz data.tar.gz   \
	> mircpio -oHar -Mdist >with-mircpio
	$ mirpax -w -M dist -f with-mirpax -x ar \
	> debian-binary control.tar.gz data.tar.gz
	$ mirtar -M dist -A -cf with-mirtar \
	> debian-binary control.tar.gz data.tar.gz
	$ GNUTARGET=a.out-i386-linux fakeroot ar rc with-aout-ar \
	> debian-binary control.tar.gz data.tar.gz
	$ md5sum with-*
	a466e2fd57cdee141fe585a43245548f  with-aout-ar
	a466e2fd57cdee141fe585a43245548f  with-mircpio
	a466e2fd57cdee141fe585a43245548f  with-mirpax
	a466e2fd57cdee141fe585a43245548f  with-mirtar
 

Voil . I got it, and even appending is possible. It supports the BSD format with special focus on DEB files, and deals with long filenames, but not symbol or filename tables (used by ranlib(1) or strange formats, respectively, but since we don t create *.a files to use with some native linker/binder/loader, we don t need that anyway).

On extraction (oh, and listing!) it deals with SYSV style filenames as well.

	$ mirtar tvf on-elf
	-rw-r--r--  1 tg       tg          4 Aug 18 16:05 debian-binary
	-rw-r--r--  1 tg       tg       1391 Aug 18 16:05 control.tar.gz
	-rw-r--r--  1 tg       tg      18135 Aug 18 16:05 data.tar.gz
	$ mirtar tvf with-aout
	-rw-r--r--  1 tg       tg          4 Aug 18 16:05 debian-binary
	-rw-r--r--  1 tg       tg       1391 Aug 18 16:05 control.tar.gz
	-rw-r--r--  1 tg       tg      18135 Aug 18 16:05 data.tar.gz
 

One of the real benefits is that you can use the front-ends interchangably for example, mirtar tzf foo.cpio.gz would work (which GNU tar can t do), and mircpio s ustar implementation, unlike GNU cpio s, is not horribly broken. Of course, there are some drawbacks: it s not GNU tar or GNU cpio, so there are absolutely zero --long-options. Some of their features are missing (but tar s -O is implemented now), so it s no replacement (but very well usable alongside it). The format called pax, committee-designed to replace ustar, isn t yet supported ironically, but that s on the TODO.

So, what do you think?

	tg@frozenfish:~/Debs/dists/sid/wtf/Pkgs/mircpio $ ll *.deb
	-rw-r--r-- 2 tg freewrt 78140 Aug 17 11:04 mircpio_20110817-0wtf2_amd64.deb
	-rw-r--r-- 3 tg freewrt 72262 Aug 17 11:00 mircpio_20110817-0wtf2_i386.deb
	-rw-r--r-- 1 tg freewrt 67446 Aug 17 18:21 mircpio_20110817-0wtf2_m68k.deb
 

Should I upload this to Debian proper? As for the licence: 3-clause UCB (and 2-clause BSD, which is a subset of it), so no problem. I m asking because the other package which I had been using for a long time and not uploaded, jupp, got uploaded recently (during DebConf) on user input (people wondered why it did not yet exist in Debian proper). I guess the old saying if it s not in Debian, it doesn t exist holds true in many parts of the OSS world. It s up to date wrt. standards btw, and lintian-clean save for two pedantic-class warnings (no upstream changelog file, no homepage link) which aren t fulfillable (could link this wlog entry as homepage). If you know Alioth you re familiar with the software formerly known as SourceForge, formerly known as GForge, currently known as FusionForge. My employer both uses it and contributes to it, we run an adapted (mostly themed, prototyping new functions that often end up in FusionForge itself, and backporting functions from FF to our production codebase ) version.

I ve backported the extratabs plugin to appease project managers and other non-technical people while we move our codebase to FF 5.1, and I did so on an installed version of the plugin rather than the source because the latter was tightly integrated with rather heavy packaging style changes.

	[ ]
	dh_builddeb
	# create fusionforge-plugin-extratabs binary package
	toplev=$$(pwd); cd plugins/fusionforge-plugin-extratabs; \
	p=$$(print -r -- $$(sed -n '/^Package: /s///p' C/control   head -1)); \
	v=$$(print -r -- $$(sed -n '/^Version: /s///p' C/control   head -1)); \
	a=$$(print -r -- $$(sed -n '/^Architecture: /s///p' C/control   head -1)); \
	d=$$ p _$$ v _$$ a .deb; \
	rm -f $$toplev/../$$d control.tar.gz data.tar.gz; \
	(cd control; find .   fgrep -v /.svn   sort   \
	    mircpio -oC512 -Hustar -M0x0B -Mgslash)   gzip -n9 >control.tar.gz; \
	(cd data; find .   fgrep -v /.svn   sort   \
	    mircpio -oC512 -Hustar -M0x0B -Mgslash)   gzip -n9 >data.tar.gz; \
	mirtar -M dist -Acf $$toplev/../$$d debian-binary cont*gz dat*gz; \
	rm -f control.tar.gz data.tar.gz; \
	cd $$toplev; dpkg-distaddfile $$d non-free/devel optional
 

The hardest part of extending debian/rules with that was to get the autobuild and dpkg-distaddfile call right. This works, even though I d call it a temporary kludge. (No need to tell me I should have used && I know. And I only shell out to mksh(1) because the inner part was already there from before, when I still used ar(1). This was slightly edited for the wlog.) In the meanwhile, apt-extracttemplates can deal with SYSV style filenames in DEB files on Debian sid, but not on Kubuntu hardy, which some people are using as Desktop OS still

Jo Shields: Why we mustn t allow smartphones to become a 2 or 3 horse race

A very popular refrain on tech sites is that the high street cannot support multiple competing phone ecosystems. It s a reasonable position to take. Do phone stores want to train their employees on six or seven different OSes? Do consumers understand the differences, and should they need to? Do app developers want to rewrite their app six or seven times? The obvious answer to all of these is no . Stores only want to train their employees once, developers want to write their app once. Choice is bad, because choice is complicated. You can have it in any colour, so long as it s black. The problem is, we need those competing efforts, for the entire market to increase in quality. Until the iPhone appeared on the market, Google s nascent mobile phone OS looked more like a poor man s Blackberry OS than what ended up shipping on the HTC Dream and later devices. Windows Phone 7 didn t ship with any multitasking at all and now the Mango update will be incorporating a multitasking model largely thieved from WebOS. iOS only just got support for updating the phone s firmware without being plugged into a host PC via USB, something which a few Android devices and all WebOS devices have always supported. Consider, for comparison, the web browser market. It would be easiest if there was only one web browser but that browser would quickly stagnate and cause pain, the way Internet Explorer 6 did when it had almost the entire market. It wasn t until upstarts like Firefox and Opera and Chrome and more started showing off their unique ideas that the entire pack started improving including IE, with IE9 supporting most of the features that the competition introduced. Every smartphone shipping today has something to offer that other devices don t and every smartphone OS shipping today has something to offer that other OSes don t. iOS has the widest app catalog. Android is Open Source (FSVO Open ). WebOS has the best multitasking, and Just Type . Windows Phone 7 offers a drastic new user interface paradigm. Blackberry OS is built for messaging tasks, and has the best sysadmin control. Symbian is well, okay, sometimes there s a time to let go but the same applies for web browsers too. Smartphones are communication devices that people use every day of their lives, and every consumer has different needs we shouldn t try to push them into an ill-fitting category, just to satisfy ourselves that it s probably only possible for three mobile platforms to succeed in the mass-market . For some people, Blackberry OS really *is* the best choice, and no matter how much you pretend, an iPhone would enhance their lives. And as for the app question tough shit. Plenty of app developers only target iOS even though Android is overtaking in the market, and if they really want to reach as many people as possible, then use a cross-platform framework like PhoneGap or some of Xamarin s products. Single-ecosystem apps are a low-effort push to reach as many people possible with minimal investment, and the only way to satisfy that class of developer is to eliminate ALL competition in the marketplace iOS-only devs are this decade s IE6-only devs. Everyone is entitled to their opinion, but I for one am sick of all the tales of doom and gloom that immediately surround any effort which isn t iOS or pure Android. We have a marketplace of ideas, which we should be celebrating, and not dumping on. I m eagerly awaiting delivery of my HP Pre 3, with all the unique possibilities it offers me which simply another Android device wouldn t have. And the big difference between WebOS and Nokia s Maemo/MeeGo efforts, for those who are still doubtful, is HP haven t spent years trying to deliberately sabotage the platform. Give it time. If I m wrong, the worst-case scenario is being lumbered with an awesome phone.

Rapha&#235;l Hertzog: People behind Debian: Peter Palfrader, Debian System Administrator

You might not know who Peter is because he s not very visible on Debian mailing lists. He s very active however and in particular on IRC. He was an admin of the OFTC IRC network at the time Debian switched from Freenode to OFTC. Nowadays he s a member of the Debian System Administration team who runs all the debian.org servers. If you went to a Debconf you probably met him since he s always looking for new signatures of his GPG key. He owns the best connected key in the PGP web of trust. He also wrote caff a popular GPG key signing tool. Raphael: Who are you? Peter: I m Peter Palfrader, also known as weasel. I m in my early 30s, born and raised in Innsbruck, Austria and am now living and working in Salzburg, Austria. In my copious free time, other than help running Debian s servers I also help maintaining the Tor project s infrastructure. Away from the computer I enjoy reading fiction (mostly English language Science Fiction and Fantasy), playing board games and going to the movies. Weather permitting, I also occasionally do some cycling. Raphael: How did you start contributing to Debian? Peter: I installed my first Debian the week slink came out. That was Debian 2.1 for the youngsters, in early 1999. The one thing I immediately liked about slink was that Debian s pppd supported RAS authentication which my university s dial-up system required. No way I d go back to SuSE 5.3 when I had working Internet with my Debian box. :) During that year I started getting involved in the German language Debian channel on IRCnet which got me in contact with some DDs. Christian Kurz (<shorty>) was working on Debian QA at the time and he asked my help in writing a couple of scripts. Some of that work, debcheck, still produces parts of the qa.d.o website, tho the relevance of that nowadays is probably negligible. While trying to learn more Perl earlier, I had written a program to produce syntax highlighted HTML for code snippets in various languages. I didn t really know what I was doing but it kinda worked, and probably still does since I still get mail from users every now and then. I figured that it would be really nice if people could just get my software together with Debian. According to code2html s Debian changelog the initial release of the package was done on a weekday at 2:30 in the morning early in 2000, and if my memory serves me correctly, shorty uploaded it shortly afterwards. I started packaging a couple of other piece of software and in the same year I sent my mail to the debian account managers to register my intent to become a DD. No new developers where being accepted at that time since the DAMs wanted to overhaul the entire process so I wasn t surprised to not get any immediate reply. Of course what the silence also meant was that the mail had been lost, but I only learned of that later when I took all my courage to ask DAM about the status of application a couple months later. Once that was sorted out I was assigned an AM, did the usual dance, and got my account late in November 2000. Raphael: Four years ago, the Debian System Administration team was a real bottleneck for the project and personal conflicts made it almost impossible to find solutions. You were eager to help and at some point you got dropped as a new member in that team. Can you share your story and how you managed the transition in the difficult climate at that time? Peter: Ah, that was quite the surprise for an awful lot of people, me included. Branden Robinson, who was our DPL for the 2005-2006 term, tried to get some new blood added to DSA who were at the time quite divided. He briefly talked to me on IRC some time in summer 2005, telling me I had come recommended for a role on the sysadmin team . In the course of these 15 minutes he outlined some of the issues he thought a new member of DSA would face and asked me if I thought I could help. My reply was cautiously positive, saying that I didn t want to step on anybody s toes but maybe I could be of some assistance. And that was the first and last of it, until some fine November day two years later I got an email from Phil Hands saying I ve just added you to the adm group, and added you to the debian-admin@d.o alias. and welcome on board . *blink* What!? My teammates at the time were James Troup (elmo), Phil Hands (fil), Martin Joey Schulze and Ryan Murray (neuro). The old team, while apparently not on good terms with one another, was however still around to do heavy lifting when required. I still remember when on my first or second day on the team two disks failed in the raid5 of ftp-master.debian.org aka ries. Neuro did the reinstall once new disks had arrived at Brown University. I m sure I d have been way out of my league had this job fallen to me. Fortunately my teammates were all willing and able to help me find whatever pieces of information existed that might help me learn how debian.org does its stuff. Unfortunately a lot of it only existed in various heads, or when lucky, in one of the huge mbox archives of the debian-admin alias or list. Anyway, soon I was able to get my hands dirty with upgrading from sarge to etch, which had been released about half a year earlier. Raphael: I know the DSA team has accomplished a lot over the last few years. Can you share some interesting figures? Peter: Indeed we have accomplished a lot. In my opinion the most important of these accomplishment is that we re actually once again a team nowadays. A team where people talk to one another and where nobody should be a SPoF. Since this year s debconf we are six people in the admin team: Tollef Fog Heen (Mithrandir) and Faidon Liambotis (paravoid) joined the existing members: Luca Filipozzi, Stephen Gran, Martin Zobel-Helas, and myself. Growing a core team, especially one where membership comes with uid0 on all machines, is not easy and that s why I m very glad we managed to actually do this step. I also think the infrastructure and our workflows have matured well over the last four years. We now have essential monitoring as a matter of course: Nagios not only checks whether all daemons that should be running are in fact running, but it also monitors hardware health of disks, fans, etc. where possible. We are alerted of outstanding security updates that need to be installed and of changes made to our systems that weren t then explicitly acked by one of us. We have set up a centralized configuration system, puppet, for some of our configuration that is the same, or at least similar, on all our machines. Most, if not all, pieces of software, scripts and helpers that we use on debian.org infrastructure is in publicly accessible git repositories. We have good communication with other teams in Debian that need our support, like the ftp folks or the buildd people. As for figures, I don t think there s anything spectacular. As of the time of our BoF at this year s DebConf, we take care of approximately 135 systems, about 100 of them being real iron, the other virtual machines (KVM). They are hosted at over 30 different locations, tho we are trying to cut down on that number, but that s a long and difficult process. We don t really collect a lot of other figures like web hits on www.debian.org or downloads from the ftp archive. The web team might do the former and the latter is pretty much impossible due to the distributed nature of our mirrors, as you well know. Raphael: The DSA team has a policy of eating its own dog food, i.e. you re trying to rely only on what s available in Debian. How does that work out and what are the remaining gaps? Peter: Mostly Debian, the OS, just meets our needs. Sure, the update frequency is a bit high, we probably wouldn t mind a longer release cycle. But on the other hand most software is recent enough. And when it s not, that s easy to fix with backports. If they aren t on backports.debian.org already, we ll just put them there (or ask somebody else to prepare a backport for us) and so everybody else benefits from that work too. Some things we need just don t, and probably won t, exist in Debian. These are mainly proprietary hardware health checks like HP s tools for their servers, or various vendors programs to query their raid controller. HP actually makes packages for their stuff which is very nice, but other things we just put into /usr/local, or if we really need it on a number of machines, package ourselves. The push to cripple our installers and kernels by removing firmware was quite annoying, since it made installing from the official media next to impossible in some cases. Support for working around these limitations has improved with squeeze so that s probably ok now. One of the other problems is that especially on embedded platforms most of the buildd work happens on some variation of development boards, usually due to increased memory and hard disk requirements than the intended market audience. This often implies that the kernel shipped with Debian won t be usable on our own debian.org machines. This makes keeping up with security and other kernel fixes way more error prone and time intensive. We keep annoying the right people in Debian to add kernel flavors that actually boot on our machines, and things are getting better, so maybe in the future this will no longer be a problem. Raphael: If you could spend all your time on Debian, what would you work on? Peter: One of the things that I think is a bit annoying for admins that maintain machines all over the globe is mirror selection. I shouldn t have to care where my packages come from, apt-get should just fetch them from a mirror, any mirror, that is close by, fast and recent. I don t need to know which one it was. We have deployed geodns for security.debian.org a while ago, and it seems to work quite well for the coarse granularity we desired for that setup, but geodns is an ugly hack (I think it is a layer violation), it might not scale to hundreds or thousands of mirrors, and it doesn t play well with DNSSEC. What I d really like to see is Debian support apt s mirror method that I think (and I apologize if I m wronging somebody) Michael Vogt implemented recently. The basic idea is that you simply add deb mirror://mirror.debian.org/ or something like that to your sources.list, and apt goes and asks that server for a list of mirrors it should use right now. The client code exists, but I don t know how well tested it is. What is missing is the server part. One that gives clients a mirror, or list of mirrors, that are close to them, current, and carry their architecture. It s probably not a huge amount of work, but at the same time it s also not entirely trivial. If I had more time on my hands this is something that I d try to do. Hopefully somebody will pick it up. Raphael: What motivates you to continue to contribute year after year? Peter: It s fun, mostly. Sure, there are things that need to be done regularly that are boring or become so after a while, but as a sysadmin you tend to do things once or twice and then seek to automate it. DSA s users, i.e. DDs, constantly want to play with new services or approaches to make Debian better and often they need our support or help in their endeavors. So that s a constant flow of interesting challenges. Another reason is that Debian is simply where some of my friends are. Working on Debian with them is interacting with friends. I not only use Debian at debian.org. I use it at work, I use it on my own machines, on the servers of the Tor project. When I was with OFTC Debian is what we put on our machines. Being a part of Debian is one way to ensure what Debian releases is actually usable to me, professionally and with other projects. Raphael: Is there someone in Debian that you admire for their contributions? Peter: That s a hard one. There are certainly people who I respect greatly for their technical or other contributions to Debian, but I don t want to single anybody out in particular. I think we all, everyone who ever contributed to Debian with code, support or a bug report, can be very proud of what we are producing one of the best operating systems out there.
Thank you to Peter for the time spent answering my questions. I hope you enjoyed reading his answers as I did. Subscribe to my newsletter to get my monthly summary of the Debian/Ubuntu news and to not miss further interviews. You can also follow along on Identi.ca, Twitter and Facebook.

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14 August 2011

Iain Lane: Dear lazyweb: Cycle touring by train

dangly bikelets Dear lazyweb, In a couple of weeks I'm likely to be going cycle touring around the North East of England. This will involve first taking a train from Nottingham. While looking at train options just now, I was reminded of a little survey that I wanted to conduct. Taking bicycles on trains in the UK can be a hit-or-miss experience. The UK's train routes are operated by a variety of train operating companies who each have different policies on taking bicycles on their trains. Some require a reservation, some do not. Some do not even allow reservations at all. There's no official database of these policies. It is up to you to check all of the companies' websites individually. As far as I can tell it is impossible to make a cycle reservation online. If you don't make a reservation, chances are that you'll be OK, but there are no guarantees you won't find yourself stranded in Bolton when none of your connections will take you. The number of spaces reserved for cycles is extermely limited. Two seems to be the most common number that a train can officially carry (you may be able to stash it in the vestibule). Even given this, it is usual to find that the cycle spaces are taken up by prams, luggage and other crap when you actually board the train, so the effective number may actually be 0. However, it is thankfully not uncommon to find staff and other passengers who are more than willing to go out of their way to help you if they see you are trying to take a bicycle onto a train. :-) Anyway, I'm interested in how this situation is in other non-UK countries. Better or worse? A lot of countries certainly have a more cycle-friendly culture I'd like to know how this kind of thing works there so that I can write a Strongly Worded Letter about how we Should Be Doing Better. (Image by onohiroki, CC-by-nd.)

Craig Small: Making peace with Network Manager

Painless they say, automatically they say. This is what the NetworkManager manual page describes the daemon. I d like to say annoying and intrusive and I know there are a lot of people out there that feel the same. The program is used to set-up network connections and provides a system tray thingy for Gnome and for simple set-ups its great. Sure, I got NetworkManager running on my laptop and we re all friends over there. It just works, it just works for my local network, wireless network and even 3G and VPNs work just like they should. This is the environment where it was designed for and it shows. What about on the server where I login using gdm? We ve had nothing but a world of pain there. It used to be bad enough when it fiddled with /etc/resolv.conf meaning DNS stopped working everytime i logged out. Every stop playing around with my settings and leave me alone option fails to do just that. It got so bad I had to use chattr to make the file immutable; so if you are tearing your hair out, then chattr +i /etc/resolv.conf is your friend. The latest version of NetworkManager takes this insanity to a new level. Now not content with messing around with my resolver files, it reconfigures my statically assigned IP address to a dynamic DNS one AND removes it when I logout. No doubt if it let it, it would muck around with resolver files too. Again, by default on a laptop this is fine. The problem is the would you leave me alone options fail to work, or mean stupid things happen like pidgin doesnt think there is a network so never logs in. So I resorted to reading more about this intrusive program and was there a way of stopping it doing what it was doing. The directory /etc/NetworkManager/system-connections looked promising as they were connections available at boot time and across all users. But then there is the funky format and wow, nothing saying what you might need versus what if you have missing makes the thing fail. What s not obvious is that if you edit your network connections and then select available to all users then your settings go into that system-connections directory and that for the moment appears to be working. It means I have my network settings configured in two places which means all sorts of fun if I change them and forget about the other. This isn t an ideal situation and network manager should start to behave properly and read the ifupdown stuff and use it but not muck around with settings if it is told to. There are options that imply they do this but they don t work. Despite the title, I don t think peace has broken out between me and Network Manager but rather an uneasy truce; I m sure that program is just sitting there thinking of what other settings it could play with when my back is turned.

13 August 2011

Neil Williams: multistrap runtime translations

Multistrap runtime message translations need updating but the manpages aren't being done this time around. More changes are likely before those get done.Current runtime translation status:

language translated fuzzy untranslated
-----------------------------------------------------
da 103 4 4
fr 54 17 40
pt 54 17 40
vi 54 17 40

http://lists.debian.org/debian-i18n/2011/08/msg00105.html
Check with the relevant debian-i18n team for your language, this is just a prompter in case people miss the mailing list post.Update: Hmm, that went to the wrong blog. It got tagged i18n but was meant for the i18n blog. Ah well, doesn't hurt for Planet Debian to see what is going on elsewhere....

Martin-&#201;ric Racine: Configuring GNOME themes for both gconf and dconf?

For a number of years, I've been making myself metapackages that pull favorite packages and pre-configure the desktop environment to use my favorite global default settings. This currently means configuring the gconf keys for the GTK theme, icon theme and background image for GDM. Until now, I implemented this by calling gconftool-2 directly in postinst as user gdm but Lintian recently started warning me that the correct way to do this would be by calling gconf-schemas or update-gconf-defaults instead. I was thus wondering, would anyone have any sample code that accomplishes this? To further complicate things, GNOME 3 has transitioned from gconf to dconf, which suggests that a slightly different method needs to be used to perform the same. Would anyone have any sample code to implement this? Thanks in advance to anyone who can help me with this!

11 August 2011

Russell Coker: Name Server IP and a Dead Server

About 24 hours ago I rebooted the system that runs the secondary DNS for my zone and a few other zones. I d upgraded a few things and the system had been running for almost 200 days without a reboot so it was time for it. Unfortunately it didn t come back up. Even more unfortunately the other DNS server for my zone is ns.sws.net.au which is also the only other server for the sws.net.au zone. Normally this will work because the servers for the net.au zone have a glue record containing the server IP address. So when asked for the NS records for the sws.net.au domain the reply will include the IP address of ns.sws.net.au. The unfortunate part was that the IP address was the old IP address from before the sws.net.au servers changed to a new IP address range, I wonder whether this was due to the recovery process after the Distribute IT hack [1], as forgetting to change a glue record is not something that I or the other guy who runs that network would forget. But it is possible that we both stuffed up. The DNS secondary was an IBM P3-1GHz desktop system with two IDE disks in a RAID-1 array. It s been quite reliable, it s been running in the same hardware configuration for about four years now with only one disk replacement. It turned out that the cooling fan in the front of the case had seized up due to a lot of dirt and the BIOS wouldn t let the system boot in that state. Also one of the disks was reporting serious SMART problems and needed to be replaced poor cooling tends to cause disk errors. It seems that Compaq systems are good at informing the user of SMART problems, two different Compaq desktop systems (one from before the HP buyout and one from after) made very forceful recommendations that I replace the disk, it s a pity that the BIOS doesn t allow a normal boot process after the warning as following the recommendation to backup the data is difficult when the system won t boot. I have a temporary server running now, but my plan is to install a P3-866 system and use a 5400rpm disk to replace the 7200rpm that s currently in the second position in the RAID array. I ve done some tests on power use and an old P3 system uses a lot less than most new systems [2]. Power use directly maps to heat dissipation and a full size desktop system with big fans that dissipates less than 50W is more likely to survive a poorly cooled room in summer. Laptops dissipate less heat but as their vents are smaller (thus less effective at the best of times and more likely to get blocked) this doesn t provide a great benefit. Also my past experience of laptops as servers is that they don t want to boot up when the lid is closed and getting RAID-1 and multiple ethernet ports on a laptop is difficult. Finally I am going to create a third DNS server for the sws.net.au domain. While it is more pain to run extra servers, for some zones it s just worth it.

8 August 2011

Axel Beckert: Finding libraries not marked as automatically installed with aptitude

This is a direct followup on my blog posting Finding packages for deinstallation on the commandline with aptitude. In the meanwhile on more alias for finding obosolete packages made it into my zsh configuration. It s an alias to find installed libraries, -data, -common and other usually only automatically installed packages, which are not marked as being installed automatically nevertheless:
alias aptitude-review-unmarkauto-libraries='aptitude -o "Aptitude::Pkg-Display-Limit=( ^lib !-dev$ !-dbg$ !-utils$ !-tools$ !-bin$ !-doc$ !^libreoffice   -data$   -common$   -base$ !^r-base ) !~M"'
And yes, this pattern is slightly larger than those from the previous posting, so here s the used filter in a little bit more readable way:
(
  ^lib
    !-dev$
    !-dbg$
    !-utils$
    !-tools$
    !-bin$
    !-doc$
    !^libreoffice   
  -data$   
  -common$   
  -base$
    !^r-base
)
!~M
It matches all non-automatically installed packages whose name starts with lib , but is neither a debug symbols package, a development header package, a documentation package, a package containing supplied commands, nor a libreoffice package. Additionally it matches all non-automatically installed packages ending in -data, -common, or -base, but excludes r-base packages. Of course you can then mark any erroneously unmarked library by pressing M (Shift-m). If you press g for Go afterwards and wonder why nothing to remove shows up, be reminded that the filter limit is active in this view, too. So press l for Limit and then Ctrl-u to erase the current filter limit of this view and press enter to set the new (now empty) filter, et voil Hope this is of help for some others, too.

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