I previously thought I'd found the perfect small, low-power system in the Fulong, but that's proving unobtainable outside of China for mere mortals. Then I discovered the Zonbu. Love at first sight (of >= 4 USB ports and PS/2). It's perfect for what I want. The question is, can I readily hack it to run the Linux distro of my choosing? Will ATA over Ethernet suck badly on it? There's only one way to find out...

I have spent almost the whole day preparing my next trip to Sicily, in the first of my two week holidays. I have installed Italy maps in my TomTom Go 510 and I have been reading about the island. I was thinking on printing all the guide I was reading, or buying a paper one, but I think that I will put all that info in a PocketPC and get it from there. It is a pity that my TomTom doesn't have a browser or PDF reader, as it could serve well as a GPS with PDA options (even bluetooth to connect to mobile phones and internet), like there are some PDAs with GPS out there.

Many people think that white-box machines (IE the cheapest no-nam PCs you can buy) are suitable for use as servers. There are several factors that make white-box machines totally unsuitable for use as a server (and IMHO unsuitable for any other task). Firstly white-box machines are not designed. A set of parts are designed, some combinations of parts are tested, but most aren’t. For example a motherboard manufacturer will test their latest motherboard design with the current video cards and a video card manufacturer will test their new cardss with current motherboards. If you have a new video card and a new motherboard then there has probably been little testing of the combination. This compares to a name-brand machine where the entire unit has been tested and found to work together. White-box assemblers (they aren’t “designed” or “manufactured”) will often use different combinations of parts for each machine that they assemble. If a video card manufacturer sells two cards with the same part number that have different chips then they may be installed in two machines with the same description. So taking an image of one white-box machine and installing it on another that was described as being identical might not work. For these reasons I have ceased using white-box machines as desktop machines or as low-end servers (EG internet gateway machines). I use second-hand name-brand machines for low end servers and for desktop machines. When comparing servers the case for name-brand systems is even stronger. Real servers have ECC RAM as a standard feature, it is possible to get white-box servers with ECC RAM - I have seen such a machine on one occasion. But the vast majority of white-box machines lack such features. See my previous posts about getting ECC RAM in a cheap machine and desktop machines with ECC RAM about some of the issues in this regard. Another feature of servers is better storage options. There are white-box server machines with hot-swap hard drives, but they are significantly more expensive than regular white-box machines - if you are going to spend that much money then it’s better to get a refurbished HP server machine at auction (HP seems to be selling a lot of almost-new server gear at auction at quite reasonable prices with warrantee). A cheap machine (typical white-box or a very low end server from a company such as HP) will have hard drives that don’t support hot-swap. Lack of hot-swap means that a hard drive failure requires that the machine be disassembled to swap the dead disk - it also means that there is sometimes difficulty in identifying which disk has the problem (the error light on a hot-swap drive is quite handy). Then the process of swapping the disk will take at least 10 minutes of hardware work before the machine can be booted up again. With hot-swap disks you can identify the failed disk via a flashing light, remove it while the server is still running, and then initiate a RAID rebuild after installing the new disk. Hot-swap disks cost more and the mounting brackets etc are also expensive, but it’s a good option to have - especially considering that disks are more likely to fail at busy times which is when down-time is least acceptable. These features make disk expansion particularly expensive for servers, people often miss the benefits of servers and say “I just bought a 3000G disk for my home PC for $2, why can’t you just do the same for the server” (I am exaggerating slightly). Another advantage of name-brand servers is remote access. There have been a variety of remote access cards that you could install in a white-box PC and also a variety of devices to digitise a VGA signal for remote KVM access, but they are all rather expensive and remove the price advantage of white-box hardware. A final benefit of name-brand hardware is that you will be running the same hardware as other people. If I was to experience a problem running Linux on a HP DL380 G4 server then I can enter that text in to Google and get many hits. If I was to experience a similar problem with a white-box machine then I would need to perform searches on each of the parts that might have a problem - which would be particularly inconvenient if I couldn’t determine some of the part numbers through software and needed to disassemble the machine first!

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Now for the real world applications. While internationalizing some programs with gettext, I found that some of them tend to use global defined variables for handling the menus (for example fluid, or hex-a-hop), usually defining some lists of structures globally, with the texts directly written on them. Something like:

const char *lines[] =  
"Line 1n",
"Line 2n",
NULL
 ;

In this case we have a problem, because if we just replace the strings by _(”string”), it won’t directly work. Remember that _ is a macro for the function gettext. In C, it just won’t let us call it from the constructor, because the string should have to be assigned statically. In C++ it will let us, but the resulting program will happen to call gettext() on them before our initialization in main(), and thus it will simply not work. I’ve made available an example on how those situations could be handled both in C and C++.

I received a private email in response to my post about getting work in another country regarding hotel prices in London. The person who sent me the message had considered London but ended up moving to Japan instead partly due to living expenses (although Japan seems unlikely to be much cheaper). The first issue concerns security of hotels. When living in hotels (for almost a year in London and about 6 months in the Netherlands there were a few occasions (IE one brief occasion every 4+ months) when I left my laptop under my bed at a hotel, but almost all the time I took it with me. At that time I aimed to have a minimal set of luggage, one large suitcase containing clothes, books, etc (things that are generally not worth stealing) and one small case containing my laptop, digital camera, passport, and other small things that are valuable or which would cause excessive inconvenience if I lost them. Also in the small case I would take fragile items. Then when leaving my hotel I would pack most of the items from the small suitcase (pretty much everything apart from the digital camera) into my laptop bag and take it with me. This limited my losses from hotel thieves to a digital camera (no incriminating pictures and I could always buy a better one) and a couple of bottles of liquor. Good hotels have a hotel safe which you can use. But for a cheap (affordable) hotel there is no such option. Hotels in London ARE expensive, but if you are prepared to lower you standard of living they aren’t too expensive. One thing to note about UK hotels is that the idea of having a toilet and shower in every room is a new concept and all the cheaper hotels lack this. It’s a standard feature for a hotel to have a wash-basin in every room, a toilet is optional, and a bath or shower is another option. There are various types of shared bathroom in UK hotels. The better ones vaguely resemble the facilities you might expect to find at a public swimming pool (large spaces, clean tiles everywhere, and a changing area in addition to the toilet and shower cubicles). The worst ones are basically what you might expect to see in a private home but with less cleaning. To get the best deals on small hotels in London you have to find an area where there are many hotels and inspect them. It is quite acceptable to ask for the key to a room so that you can inspect it and determine if you want to rent it. One area where I lived for some time in London is near Victoria Station. Victoria is one of the largest stations in London, it has both a Tube (underground/metro for trains within the city) and a British Rail (for travel to other parts of the country) station. Victoria Station also had facilities for checking in to a flight and having your checked luggage delivered to Gatwick airport via the Gatwick Express. This was really convenient, you can check your luggage and then do some last minute shopping before going to the airport! I’m not sure if they still do this though (comments appreciated). Another good thing about Victoria Station is the large shopping area which included a tourist information centre and a store that sold freshly baked bread. Often in the morning I would buy bread from the section that had the most steam coming from it (which was the most freshly baked) before catching a train. Victoria Station is quite near many of the places you want to visit in London so I could walk to the British Museum and other places that are worth visiting (this depends on how fit you are). But the real reason for staying there is that the were many cheap hotels in the area. I could just walk down a street and know that I could find a room at one of the hotels. One feature of UK hotels is that they almost always include free breakfast as part of the deal (with no option to exclude it). Of course this means that if you are capable of eating a significant breakfast and then skipping lunch then you can save some money. A down-side to cheap hotels is that they almost never have a telephone in your room (just a pay phone in the hall), and if they do have a telephone then it will be wired in. Before wireless net access became common this was a problem as you couldn’t use a modem. More expensive hotels had an extra socket for a modem. In London there is a significant number of people who stay in hotels from Sunday night to Thursday night with their company paying (so they don’t stay in the cheap hotels). This means that most of the good hotels have cheap rooms on the weekend. So while living in London I would often stay at a good hotel on the weekend to get net access (and a few days in a luxury hotel at a cheap rate is a good change from a cheap hotel). Nowadays wireless net access is common so it would be easy to find a free access point anywhere in London and there would be no need for this. But the possibility of getting cheap hotel rooms on the weekend is something to keep in mind. One benefit of this was when I had an employer paying for my hotel bills from Sunday night to Thursday night (as part of a deal to placate my colleagues who complained about working at the other side of London). I spoke to the hotel manager and suggested that having me check out every Friday and have the room empty on the weekend was not good for them and that they should offer me a significant discount to stay 7 days a week - they made me a good deal! At that time I had the lowest cost of living apart from when I lived with my parents while the hotel in which I stayed was quite comfortable (a large comfortable room with toilet and shower and a good hotel breakfast). Moving to the Netherlands was quite easy for me as I was staying in hotels. All I had to do was to pack my suitcase, check out of the hotel, and catch the flight. One significant advantage of living in hotels is that you can easily move to another region or country. This gives the possibility of taking advantage of career opportunities that would not be possible if you owned a house and would be difficult if you rented an apartment. When in the Netherlands I ended up staying in hotels of the Bastion chain (a chain or franchise of business hotels). I stayed in a couple of other hotels first and wasn’t particularly happy but with Bastion hotels I was always happy. I arranged a deal of a small discount in exchange for not getting the breakfast that was normally included (I like to sleep in and the Dutch breakfast didn’t appeal to me). One significant benefit of the Bastion hotels over London hotels was the size. The smallest room had two single beds, a large Dutch-style bathroom, two chairs at a desk that spanned about 3M of a wall (with multiple power sockets and a phone socket), and a good TV. At the time the hotel would play two movies over the TV system every night from video cassette. The videos played on the TV in the restaurant and in the rooms (if you selected the appropriate channel). Once I became known to the staff they would do nice things such as playing the movie I requested (instead of the scheduled one) and pausing the movie when I finished dinner so I didn’t miss anything while walking to my room. Also instead of giving me a free newspaper every day (in Dutch) they gave me some free drinks vouchers every week. Once you become a regular customer at a hotel the staff are always willing to change the deal to make you happy - even when it’s a chain. One of the convenient factors of living in a business hotel is that they are located near business areas. I spent several months living in a Bastion hotel that was about 400M walk from the office where I worked. That was particularly convenient when the network broke at night - I could just walk back to the office to fix it! The deal I had with the Bastion hotels made them about 50% more expensive than the (fairly luxurious) two bedroom apartment that I later moved to. So hotels are expensive and living in them is only an option if your employer pays for it or if you work in an industry where pay is reasonably good. Given that the vast majority of people who read my blog work in the computer industry (and I suspect that they are better paid than average) this should be a viable option.

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So, depending on who you talk to, we've got about 9 weeks to go, or maybe 8 weeks. It all depends on whether we can have our way and have a caesarean on the 8th of October. Of course, the baby may have other thoughts on the matter as well... We've had our last planned house guest until Sarah's Mum and Aunty arrive, so we've put the mattress in storage and donated the bed frame to Goodwill. We've acquired a crib (I keep wanting to call it a cot) and a changing table/chest of drawers and put them in place in the baby's room. Last night we bought a car seat. I think the only major item left to get is a stroller. Sarah's pregnancy is still going well. The baby's still extremely active, and has had the hiccups quite a few times in the last week. Apparently that's him trying to breathe. I'm somewhat surprised they don't drown in there trying to do that... Speaking of breathing, our overly cautious obstetrician wanted Sarah to have two shots of steroids, to aid in the baby's lung development "just in case" he was born (or had to be delivered) very early. We felt it was somewhat unnecessary, but thought we'd be kicking ourselves if something happened and we didn't do it. There didn't seem to be any outrageous adverse effects from doing so, so we went along with it. Twice in a week (the second time today) Sarah's had blurry vision followed by a headache, so she called up the hospital today when it happened, and they told her to come in and get checked out. We spent about 4 hours in labor and delivery this afternoon. It turns out the reason they wanted us to come in was because the symptoms could be a sign of preeclampsia. The tests proved otherwise, and they couldn't really offer an explanation for what was going on other than migraines, so they eventually sent us home again. It was nice to get a preview of hospital's labor and delivery ward.

A friend recently asked for advice on a “REALLY small laptop/word processor thingy that would pretty much fit into a (big) pocket, and that only needs to write/word process“. The first problem here is that most people associate “word processing” with desktop publishing and document management. Programs such as MS-Word are considered as having the features required of a word-processor (which includes spelling and grammer checking/correcting, annotations, colours, etc). Programs that have all those features take a lot of CPU power. A Pentium-4 system might be considered the minimum requirement for running a recent version of MS-Word. But a hand-held device can’t have such a powerful CPU (it’s too small to be able to dissipate the heat from such a CPU or contain batteries that can produce enough power to tun it). The next problem is the issue of screen space. A VGA resolution screen (640×480) is regarded as high resolution in the PDA market. Such a resolution does not work with a word-processor that has three toolbars at the top of it’s screen and a paperclip taking up space at the bottom right! I’m sure that everyone who was using computers in the early 1990’s can recall the minimal word-processing programs. One thing to consider is that 640×480 in a 15 inch CRT screen is much more useful than 640×480 in a hand-held device as the larger screen can have fewer pixels per character and therefore display more text on the screen. An added complication is that there are two methods of input for PDAs. One is to have a hardware keyboard (which may be a separate device or may be part of the PDA) and the other is to have a keyboard displayed on the screen. A hardware keyboard makes the device larger and a software keyboard takes up precious screen space (you just can’t win). My PDA is an iPaQ model h3900. It has 64M of RAM, 32M of flash, no hardware keyboard, and a screen resolution of 320×240. I have done some serious writing on my iPaQ (including writing an entire article for Linux Journal) and it works reasonably well. For serious writing you can produce plain text on a PDA and then easily paste it into your program of choice on a PC later (PDAs generally support connection to a PC via serial port and/or USB). The challenge is editing files that originate on a PC using a PDA. Generally I try and use HTML and TeX for my formatted documents so the text versions of those formats are easy to edit once you have learned them. Taking data from a MD-Word file, editing it on a PDA, and then taking it back to the PC would cause many problems and probably wouldn’t be worth attempting. Recently I have been using my iPaQ for writing notes about email and blog posts that I will write. If I get an idea then I immediately write some notes about it on my iPaQ and then usually type it again instead of downloading it. For example the notes for this post were “write about RAM, storage, and screen resolution”. Often getting the initial ideas to start writing is the hard part. Writing a 500 to 1000 word blog post or message is easy once I have the ideas. If I was going to buy a new PDA now I would prefer one with a hardware keyboard, the loss of screen space for a keyboard on the touch-screen is a serious impediment to writing. The maximum amount of text that can be displayed on the screen at any one time limits the complexity of what I work on (see my post about monitors for developers). Another factor is the fact that for small notes the amount of time taken to remove the stylus from it’s bay is greater than the amount of time saved by using it. So I end up writing small notes using my finger-nail on the touch-screen which is significantly slower than using a keyboard (even the crummy ones that PDAs have). Of course the keyboard would still have to be QWERTY and have raised keys so that I can touch-type. I haven’t investigated this seriously as my iPaQ is good enough to last me for another year or two at least and I’ve got an unused spare iPaQ to replace it when it fails. But if anyone has any recommendations of Linux based PDAs with keyboards then I would appreciate some comments.

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Last thursday and friday, I spent around eleven hours in the InterCity Express (ICE) of Deutsche Bahn. I was online, using Simyo GPRS, during this entire time. Thanks to the cellular network repeaters in ICE’s coach 3 and 23, this has worked reasonably well and has cost me EUR 5,27 - in a tariff with no basic charge and no commitment. I really like that, because this usage of the mobile cellular network would have cost about fifty times more just a year ago. Thanks, Simyo, E Plus and the other E Plus resellers who have made the first step to reducing the cost of mobile Internet in Germany. A few technical notes:

• The repeaters in the ICE coaches do only repeat GSM and thus GPRS, but not UMTS. It is advised to lock the UMTS card to GPRS when using Internet from inside the ICE, since the card will otherwise move back and forth between UMTS and GPRS millions of times, which will always result in more than just a few seconds outage. It is much better to live with GPRS’ abysmally large latency.
• I took the opportunity to empty my still-active, old, GPRS only, Simyo SIM which still holds like fifteen Euros. I suspect that I’ll need two more trips of this magnitude to successfully get rid of the amount on that prepaid card.
• I need an external antenna for my UMTS card - it worked really really bad in my mom’s apartment right in the middle of Hamburg.
• There seem to be a number of independent issues in Debian sid (the reason why I am blogging this in English): The connection occasionally hangs (a couple of times an hour) and does not come back by itself. Often, poff/pon is enough, but sometimes it is necessary to pull the UMTS card (an Option 3G PC-Card Datacard) and to re-insert it since there was no answer any more on ttyUSB0. Very annoying.
• The Option 3G Datacard behaves differently depending on the SIM that is inserted. With my older, GPRS-only Simyo SIM, the response to AT+CPIN? is “SIM PUK2” after sending the PIN to the card, while it is “SIM PIN2” in the same situation with the newer UMTS-enabled Simyo SIM.
• chat(8) sucks badly, because it doesn’t seem to elegantly handle this case - no regexps, no if/then, every command sent needs to generate exactly one answer from the card, everything else is an error after timeout.
• When I do this more often, one of the now available flat rates (or, for starters, a 5 GB commitment tariff) for like 20 Euros becomes attractive.

Free software projects are informal (though becoming more formal) institutions that function in multiple capacities. Foremost, they are sites that facilitate the production and distribution of technology but they certainly allow for and produce all sorts of other social facts and processes. And one of the most important is that free software projects function as quasi-educational institutions that are structured quite differently from formal educational institutions. And this blog entry by Justin Podur that reviews a book by Alfie Kohn of alternative eduction, reminded me just how much F/OSS projects are informal educational spaces but deviate significantly from traditional learning. I have more thoughts on the type of “schooling” F/OSS allows but since I am moving to my new apt. in a few hours, it will have to wait until later.

Debian Revolutions ... begin with small steps ... ... let's see if the one I'm seeing right now will be one of those. Since ages the collab-maint project on Alioth has been configured so that all DDs can commit to its SVN repository. I've always thought this is a good idea and I've always wanted that to be true for all Alioth's collaborative maintenance project, rationale being always the same: DDs are lazy, if I have a patch ready there is nothing more valuable than the ability to commit it right now (together with an appropriate changelog entry of course!). At Debconf I chatted a bit about that with Sam and Raphael, and we started thinking about how to make that wish a reality. As a first step the Alioth admins agree on giving DD-wide commit permissions to every alioth project asking so. Let me repeat: you can widen to the whole DD body the commit permissions of your collaborative maintenance project on Alioth just asking the alioth admins. It's quick and easy, and I'm confident Debian as a whole will benefit for mass adoption of this good practice. Raphael has proposed that for adoption to the Python and Perl modules maintenance groups, and it's now implemented for the OCaml maintenance group. Ask that for your beloved collaborative maintenance project! The next step is to patch the GForge running on Alioth so that project admins can enable such a setting by themselves: I volunteered to work on that, but I'm a bit swamped with other Debian-related stuff, help would be much appreciated!

Salon.com recently reviewed Zonbu, a highly compact general-purpose computer with no moving parts. Zonbu's key features are its incredibly low power consumption, network-connected storage and that it works right out of the box without any installation. Under the covers, it's a Gentoo Linux installation with mainstream open source apps such as OpenOffice and Firefox.

Zonbu and its skins — high-powered dressing for a low-power device Price-wise, you can get the Zonbu for as little as $99 if you commit to two years' subscription to the network storage. Understanding the open source ethos, Zonbu also offer the box without any tether for $250. As with the Mac mini, supplying the keyboard, mouse and monitor is up to you. Preloaded with an office suite, email, IM, web browser, multimedia player, games and Skype, Zonbu is aimed at being a general computing appliance. You can't install anything else on it, but then again, that way you can't break it easily either. It sounds the sort of thing I'd be happy leaving with non-technical family and friends. Storage with Amazon S3 Low-power solid state devices are nothing new of course, there are a variety available, and things such as the NSLU2 have been in production for some years. The novel thing about the Zonbu however is in how it manages its storage. The Zonbu has 4GB of compact flash storage on board, which it uses as a cache for Amazon's S3 storage network. All your files get encrypted and sent to S3, and are retrieved when you need them. One really neat consequence of this is that you can get at your data via the web any time you want. Secondly, it gives me some sense of security for my data. I don't know if Zonbu will give me the 'keys' to my data on S3, but it wouldn't be hard for them to provide an easy way to migrate out. Either way, S3 is a place I'd trust with my data. Why Zonbu is important Windows, and to some extent, Mac OS X, are becoming the needy children of computing, always tugging on your arm and asking you something. In contrast, Zonbu looks like a great step towards "appliance computing". Its features are more like those you'd expect from your phone or cable TV provider:

• it's a black-box appliance that users don't need to care about, with little or no vulnerability to malware
• the real value of the product is in the network
• the system is upgraded as part of the subscription

Zonbu has the potential to change domestic computing. The low price point lowers the barrier to computer ownership. Low maintenance needs lower the technical barrier to entry and use. And Zonbu's a green and economical technology, yet as useful as the full power version. As a company, I feel Zonbu to be a well-intentioned player because of their strong support for open source, and the ease with which you can get at your data despite its appliance nature. I hope they continue to develop in this open data direction. Zonbu itself probably won't attain ubiquity, but it will change the marketplace and open up a new category of network-connected appliances for the home. Further reading

• Zonbu home page
• Gizmodo hands-on review of Zonbu. I love that the first comment is a question about whether it can run vi or emacs...
• Real life with the Zonbu Mini-PC. Very detailed blog of a Zonbu user.
  
• Dress up your Zonbu. Get rid of the drab default exterior with some amazing-looking covers

Anyway, back to pure Linux stuff. A while ago, the Ubuntu Technical Board were asked to take a look at Automatix. I've finally got around to doing so, and here are my initial conclusions. I'd appreciate any factual corrections, and note that at this point this is my individual opinion rather than any sort of official statement.

Automatix is a combination system configuration/package installation
tool, aimed at making it easy for users to install features like
graphics drivers, media codecs and software not distributed as part of
the Ubuntu distribution. It is provided as a .deb file containing a
python GUI frontend that calls out to a shell backend. The frontend
parses an XML file which contains module descriptions and function
names for installing and uninstalling modules, with these functions
being part of the shell backend. An install module will typically
check whether another package manager is running, and if not either
install a set of debs or download and manually install a
tarball. Uninstall modules generally remove the same software or clean
up the manually installed files.

The following is a list of identified issues with the current version
of Automatix - it is the result of a few hours of investigation, so
may not be complete.

• Automatix is, in itself, a poor quality package which fails to
  conform to Debian or Ubuntu policy.
  
  
  • It is inappropriately flagged as belonging to base
    
  • Depends on essential packages
    
  • Has a short description of more than 80 characters and no long
    description
    
  • Provides no email address in the maintainer field
    
  • Contains no copyright information in the standard locations
    
  • Ships a TODO file as a control file
    
  • Provides no man pages
    
  • Ships files in /usr/etc
    
  • Contains many files inappropriately flagged as executable
    
  • Changelog is in /usr/etc/automatix2/ax_data ?
  
  These issues are primarily cosmetic and in themselves are unlikely to
  cause any harm to the system.
  
• In debug mode, automatix will write files to your home directory as
  root. Again, more of an irritation than anything dangerous.
  
• Provides platform-specific data in /usr/share. Potentially an issue
  if /usr/share is shared between multiple architectures, but since
  Automatix is x86/amd64 only probably not a real problem.
  

• #!/bin/bash
  #created by arnieboy 
  foo= gksudo -u root -k -m "enter your password for gedit root access" /bin/echo "Do you have root access?" 
  sudo gedit $NAUTILUS_SCRIPT_SELECTED_URIS

  appears to be an attempt to ensure that the user has sudo rights. This
  will break if timestamp_timeout is set to 0 in sudoers - gedit should
  be run directly from gksudo. This is repeated in more than one
  place. The assumption that sudo will not need to prompt appears
  prevalent throughout the code.
  
• catagory_data.xml - nitpick, but should be category
  
• "Please NOTE that downloading and installing w32codecs, libdvdcss2
  and other non-free codecs without paying a fee to the concerned
  authorities constitutes a CRIME in the United States of America"
  
  Somewhat dubious legal advice - the issue has nothing to do with fees,
  and isn't just limited to the USA.
  
• Automatix checks that other package managers aren't running at
  startup (by grepping for a static list of application names in the
  proces list), but doesn't enforce this by carrying out any locking of
  its own. This leaves Automatix open to race conditions.
  

• if ps -U root -u root u   grep "dpkg"   grep -v grep;
     then
       killall -9 dpkg

  May well leave the system in an inconsistent and unbootable state, and
  is carried out without warning. This is entirely unacceptable and will
  leave a stale lockfile in any case.
  

• function reloadnautilus  
         killall -9 nautilus
   

  Not actually used anywhere, but could potentially lose user
  information without warning.
  
• Most install functions contain a sleep statement for no obvious
  reason. They then call dpkg_check, which sleeps again. It's not at all
  clear what this is meant to be doing.
  
• Passes --assume-yes to apt-get, which will (as a result) happily
  remove packages without giving the user an opportunity to
  intervene. This is especially bad when removing Automatix modules -
  any package that depends on one of the packages being removed will
  also be uninstalled, even if the package was originally installed via
  something other than Automatix!
  
• Has no internal dependency management. Unable to keep track of why
  packages were installed, so prevents the removal of the multimedia
  module because that would remove sections of other modules without
  explicitly removing that module. Installing swiftfoxplugins will pull
  in several plugin packages, but removing swiftfoxplugins will not
  remove them even if nothing else depends on them. Also means that
  package installation and uninstallation have to be manually kept in
  sync - uninstall will not always remove all packages that were
  installed.
  
• Has no concept of file tracking, so will just remove entire
  directories. Makes no attempt to ensure that a user-installed version
  is not already installed in the same location, so effectively assumes
  that the /opt namespace belongs to it.
  
• Will remove Ubuntu repository packages in favour of tarballs with
  no warning.
  
• Setting ctrl-alt-del to open gnome system monitor will destroy any
  existing user configuration for run_command_9
  
• Installing streamtuner will create a world writable directory in
  /opt/ripped with no sticky bit, allowing users to interfere with other
  users' files.
  
• mplayerplugin moves totem plugin files to a backup, but does
  nothing to prevent package upgrades of totem replacing them.
  
• Only updates the java link after installing new java, not the rest
  of the java alternatives
  
• amsninstall installs tls libs that are never removed, copying over
  the ones in the tcltls package. This means that the md5sums in the
  tcltls package will no longer validate.
  

• sudo ln -s /usr/lib/libesd.so.0 /usr/lib/libesd.so.1

  is really not
  such a good idea.
  

• ln -s /tmp/.esd-1000 /tmp/.esd

  looks like it'll only ever work for
  the first user on the system, and there's nothing to recreate it on
  boot.
  

• sudo sed -i "s/^vboxusers\(.*\):$/vboxusers\1:$AXUSER/" /etc/group

  - assumes that the system isn't using some sort of user directory
  service.
  
• installs truecrypt suid root - not ideal, given its less than
  stellar security record
  
• Unmounts filesystems without checking to ensure that the unmount
  succeeded.
  
• Deletes lines from fstab and replaces them with device nodes
  rather than uuids.
  
• Includes acroread 7.0.9, despite the new Acrobat license appearing
  to grant no right to redistribute.

Conclusion:

Automatix exists to satisfy a genuine need, and further work should be
carried out to determine whether these user requirements can be
satisfied within the distribution as a whole. However, in its current
form Automatix is actively dangerous to systems - ranging from damage
to small items of user configuration, through removing user-installed
packages without adequate prompting or warning and up to the (small
but existing) potential to leave a system in an unbootable state.

The current design of Automatix precludes any reasonable way to fix
some of these problems. It is attempting to fulfil the role of a
high-level package manager without actually handling any sort of
dependency resolution itself.

A more reasonable method of integrating Automatix's functionality into
Ubuntu would be for the Automatix team to provide deb files to act as
installers for the software currently provided. These could then be
installed through the existing package manager interfaces. This would
solve many of the above problems while still providing the same level
of functionality.

In its current form Automatix is unsupportable, and a mechanism for
flagging bugs from machines with Automatix installed may provide a
valuable aid for determining whether issues are due to supported
distribution packages or third party software installers.

Often there are possibilities to earn more money or gain valuable experience by working in another country. I learned (and earned) a lot while working in London and Amsterdam and recommend travelling if you get the opportunity. There are two ways of getting work in another country. One way is to work for a multi-national company and get transferred, this gives benefits of having the company sort everything out for you (creating a bank account etc). But it isn’t an option that is open to many people. Getting a job directly in another country is in some ways more difficult than expected and in some ways easier. Here are some of the factors that make it easier:

• Once you arrive in your destination country it’s usually easy to get work if the economic conditions are good. When choosing a country to migrate to and a time to migrate you will generally make sure that the economic conditions are reasonably good (or at least demand is greater than supply for your industry sector).


• It’s widely believed by employers that employees from other countries have valuable experience to bring, due to working conditions being different in other countries. I am doubtful of this (but I don’t complain when it helps me get a job).


• Employers often believe that employees from a long way away are very highly motivated and work really hard. I believe that this is correct as it applies to the employees that they get (EG Australians in the EU work really hard). Not that Australians in general would work harder than Europeans, but people who are willing to travel so far for their career will be motivated and people who have recently arrived in a country where they have few friends and no relatives have less things to distract them from work.

Here are some of the problems that you will face:

• Different expectations of employers. For example in Australia a university degree is not really required while European employers demand it.


• Getting a bank account. When I arrived in the UK I had trouble getting a bank account due to money-laundering laws. A passport was not sufficient and I needed proof of address, but renting an apartment without having a bank account was difficult too… I ended up getting an accountant to recommend me to a bank. Apparently the easiest way of doing this is to get an Australian bank that is part of a multi-national banking group to get their UK equivalent to set up an account before you leave Australia. Also I know people who had problems getting a Dutch bank account (fortunately there is the PostBank which deals with everyone). The UK laws may have changed in the last 8 years, but it’s the sort of problem that can get you in any country - as you can’t get paid without a bank account it’s serious!


• Renting an apartment. I think it’s best to plan to live in hotels until you get a job that will last a while, then you can live reasonably close to your work. Also landlords will often want to know where you work before deciding whether to accept you as a tenant. I lived in hotels in the UK for almost a year and never rented an apartment because of this. It’s not a problem if the stuff you need can fit into a couple of suitcases.


• Learning how to save money. Little things like bulk purchases of train tickets can save significant amounts of money. It’s the sort of thing that locals learn by osmosis but foreigners can take months or years to learn them. This is especially a problem when you don’t speak the local language and discount vouchers have fine print.


• Catching a taxi. Taxi drivers generally only speak the local language and if you don’t speak it then you will have problems. Showing a taxi driver a laptop screen with printed directions and a map helps.

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Matthew: Thanks for the followup and the summary of the MacBook status wrt power consumption. I’m running a 2.6.22 kernel with the hrt patchset and a set of patches including your patch to appletouch. Your patch works great and the trackpad’s behaviour is a bit better with it. I know pretty well what the problems are on my machine, but your summary will probably be useful to a lot of people. I know some of the issues can be fixed or worked around and others cannot. Also note that I can get something like 3h45 out of my battery under OS X with my standard workload, which is pretty good. If OS X can do that, there’s no reason Linux can’t, however bad Apple’s choices are wrt hardware. And to make it clear once again, my previous post didn’t criticize the C-states or anything else, but the fact that I see PowerTOP being used more as a blame shifting tool than as a debugging/profiling tool. Though I maintain that UHCI suffers from a bad design, OHCI is a much, much better spec.

Xen Migration This afternoon I mostly migrated Xen guests from their old host to their new. (As part of a an upgrade of facilities. Upgrading in place would have been much fiddlier and more annoying!) The migration took almost three hours, which was longer than anticipated but shorter than I'd feared. In the future I'll know to do it differently, but I managed to script it fairly well after the first couple were done manually. Everything appears to be working correctly so I will soon nip out for some high quality beer. Xen Help?

One thing that I wanted to do with the new host was track bandwidth usage upon a per-guest basis. This should be possible with something like vnstat - however solutions counting traffic by interface name are not a good mesh with Xen - since by default a guest will have an interface with a name like 'vif20.0' - and no means of mapping that to a specific guest. Each of my guests has been allocated three IPs which are defined like this in the Xen configuration file:

vif = [ 'ip=1.2.3.4 1.2.3.5 1.2.3.6' ]

This works prefectly. This also works:

vif = [ 'ip=1.2.3.4,vifname=foo 1.2.3.5 1.2.3.6' ]

Unfortunately anything else I've tried to give each IP a static interface name fails. I've seen reports of this online but no solutions. Given a configuration file like this the Xen guest doesn't receive any traffic upon the second + third address:

vif = [ 'ip=1.2.3.4,vifname=foo1',
        'ip=1.2.3.5,vifname=foo2',
        'ip=1.2.3.6,vifname=foo3' ]

Any suggestions welcome.

Julian: You don't need autosuspend support to prevent UHCI from generating interrupts - you just need your hardware to be idle. The reason you're getting interrupts is that a USB device wants to send information. There's no way to get this information to the kernel without generating interrupts or polling - and polling is even worse, since it guarantees you'll be producing wakeups even when there's nothing to send.

If you're on a Macbook, the largest number of USB interrupts is probably from the Bluetooth controller. Either hciconfig hc0 down, or load hci_usb with the isoc=0 option. The other Macbook issue is that the trackpad will carry on sending updates even though there's no input - I wrote a patch to fix this, which ought to be in git now. These have nothing to do with the UHCI spec.

Why are C states so important? They allow the CPU to turn parts of itself off. However well designed your CPU, turning parts of the processor off is going to save power. Of course, this can only be done when the system is idle (code doesn't run so well on disabled execution units). It's also inevitable that there's going to be some latency in reenabling these portions of hardware, so you only want to enter them if you know that the processor is going to be idle for a significant (like 20ms or more) amount of time.

In C4 state, a modern Intel CPU will draw somewhere in the region of a Watt. There's absolutely no reason why a modern desktop shouldn't be spending most of its time idle, so we should aim to be hitting C4 as much as possible. It's low hanging fruit, and Powertop lets us identify most of the things preventing us from getting there. Processors are always going to be able to save power if they're idle. It's an entirely worthwhile project.

For what it's worth, the ULV Core 2s will max out at about 10 Watts, which isn't bad - sadly the Macbook Pro contains a T7600, which goes up to 34W. The last-generation Powerbook G4s with 7447As drew in the region of 20 Watts - Apple seems to think its customers prefer performance to low power consumption, and I don't think you can blame Intel for that (especially since you can get an LV 1.6GHz Core 2 Duo with a TDP of 17W, giving you rather more performance than the G4 Powerbook while consuming less power)

A recent thread which started on the Debian Release mailing list caught my eye this week. I attempted to aid the migration of this thread to the debian-ipv6 mailing list, which is really a better place for this and sorely in need of controversial topics for discussion. It is interesting how people can so blindly decide that broken things should be destroyed. Repair often appears not to be an option, even for a long-term, wide-reaching effort like this, though we are all working on open-source software! In this case there are an unknown number of less fortunate people in the world who are located behind some kinds of broken DNS infrastructure which discards 'AAAA' lookups. Of course 'AAAA' lookups are attempts to resolve a name to an IPv6 address, and the resolver in a 'modern' libc (i.e. one from the last five years or so :-) will try to retrieve an IPv6 address before it attempts to resolve a name as IPv4 with an 'A' lookup. That is how the standard is written, so if you want to comply with the standard you have to do it that way. Other things also interfere, but this element of the specified behaviour seems to cause the most annoying and pointless whingeing I have heard. I suppose that the people who want working IPv6 make it so, and do not have problems with this behaviour. But it seems that people who are behind this kind of broken DNS either disable IPv6, or they have to whine about IPv6 being turned on by default, and can't we please all go back to the good old days. What's wrong with IPv4 anyway? Doesn't NAT solve all of it's problems? Are we sure this new (heh!) technology is safe? Fortunately some people are so good at making their pain felt by other people that they can get other people to do their work for them. So Mithrandir has written a nice elegant patch for libc6 so that it won't do the IPv6 lookups unless you have a usable IPv6 configuration. I've filed bug #435646 against Debian to get this included, but Aurelian Jarno justifiably wants a few people to test it a bit harder... So I've taken the original patch and tweaked it to apply against current libc6 sources (2.6-5) and tested it for myself. It works as desired, as far as I can see, when comparing behaviour with an unpatched system. The patch is attached to the bug report, of course. Perhaps some other people out there can put a wee bit of CPU into testing this for other environments so that we can make life easier for those people with no time / inclination to use IPv6, to ensure that they don't just disable it because it is making life too painful for them in it's current form? How to build libc6 for fun and proft If you have appropriate deb-src URLs configured, and are running Sid, then the following will let you build a local copy of libc6 with the patch. This is probably better testing than if I just make my packages available (which are only i386 in any case).

apt-get build-dep glibc
apt-get source glibc
cd glibc-2.6
debian/rules unpack
cd build-tree/glibc-2.6
wget http://tinyurl.com/3xzm3o
patch -p0 <glibc-only-lookup-ipv6-if-it-makes-sense-debian.patch
cd -
dch --newversion 2.6-5+v6 "Apply IPv6 Resolver Sanity"
fakeroot debian/rules binary

Wait a few hours for it to build... Install... And then confirm that this only does 'AAAA' lookups if (when) you actually have a global or site scoped IPv6 address. When you only have a loopback or link local IPv6 address then you should only see 'A' record lookups. Step 3: profit! Whoops! I forgot the fun bit: please update the bug report :-) What the patch does In my opinion this is quite an elegant solution from Tolleff. He has picked a single characteristic of the IPv6 interfaces to further refine whether the IPv6 configuration of some interface is actually usable. With IPv6 it is much more common to have multiple addresses assigned to a single interface. Interfaces are automatically configured with a link-local address which is not globally routable, and the loopback interface is also configured with the IPv6 equivalent of 127.0.0.1 (which is "::1"). To get a usable IPv6 setup you will also end up with a more widely usable address. In most cases this will be a global address, meaning that it is (in theory) globally routable from other people who also have global addresses, or you could have a "site" address, which is the IPv6 equivalent of RFC1918 addressing. The patch considers that for the purposes of name resolution, it will be pointless to do AAAA lookups unless you have an address of the second kind. This means that people behind broken DNS won't be impacted unless the try and set up IPv6, and people who don't try and set up IPv6 won't get the 'hesitation' while their system attempts to resolve each address in IPv6 space first. It will also mean that when people start to enable IPv6 around them, their setup will continue to work correctly.

I’ve just reviewed my web stats from last month. Here are what appear to be the most popular posts:

1. Committing Data to Disk - about how RPM and DPKG don’t use fsync() the way I believe that they should. Surprisingly popular (more than twice as popular as #2), maybe the developers of both RPM forks and dpkg were repeatedly checking for comments.


2. Terrorism Foolishness - found by StumbleUpon.com and got lots of traffic from there. More than twice as popular as #3.


3. Prius vs Small Non-Hybrid Car - a little contentious as some Prius owners think I should compare the Prius to a Camry. I will visit a Toyota dealer soon to investigate this matter in more depth. Note that this is a post from June that was one of the most popular reads for July!


4. Tevion MP4 Player Model M6 - a Review - review of an MP4 player that didn’t satisfy me.


5. Installing Xen DomU on Debian Etch - from January but still getting read!


6. A Support Guide to Xen


7. Buying a Laptop From Another Country


8. Xen and Heartbeat - another from June.

It seems that most readers of my blog come from Planet Debian. So the above seems like an indication of what people on that planet want to read.

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In case you think that greylisting might have some disadvantages but give you also some benefits, you probably have thought about to use greylisting with some conditions. For example if you checked some parameters of the mail and you (or better your mailsystem) guess it may be spam, greylisting could be very usefull.
Until now, I was using plain policyd-weight. But mails with $REJECTLEVEL <= score <= $DEFER_LEVEL where in some conditions defered (see policyd-weight default) and if they come back with the same conditions, they will be defered twice. So it makes sence to me to greylist them and if they return within $DEFER_LEVEL, they will pass cause the greylist will allow them.
At first let’s create a restriction class which we can call from policyd-weight within main.cf of postfix:

# restriction class for use with polw (DEFER_ACTION)
smtpd_restriction_classes = greylist
greylist = check_policy_service inet:127.0.0.1:60000 To call postgrey for $REJECTLEVEL <= score <= $DEFER_LEVEL you need to make use of the restriction class “greylist” and let $DEFER_STRING match all defer strings, to get them all greylisted:

# echo “\$DEFER_STRING = ‘NOT’;” >> /etc/policyd-weight.conf
# echo “\$DEFER_ACTION = ‘rc:greylist’;” >> /etc/policyd-weight.conf
# /etc/init.d/postgrey restart Also you may have a look into The DNSBL countries.nerd.dk. This might be a way to score connections comming from well known spamming countries. But keep in mind, that there may also legitim mails comming from those! ;) planet, policyd weight, Postfix, spam