X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/0932d1479ea12acb79138d4aeadb83f639ea0ce2..0eae61fd9783f8eadf6d9848106c6d24fb9ff838:/blog/index.rss diff --git a/blog/index.rss b/blog/index.rss index f6fbda990e..889423978a 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -6,6 +6,326 @@ http://people.skolelinux.org/pere/blog/ + + Automatic upgrade testing from Lenny to Squeeze + http://people.skolelinux.org/pere/blog/Automatic_upgrade_testing_from_Lenny_to_Squeeze.html + http://people.skolelinux.org/pere/blog/Automatic_upgrade_testing_from_Lenny_to_Squeeze.html + Fri, 11 Jun 2010 22:50:00 +0200 + +<p>The last few days I have done some upgrade testing in Debian, to +see if the upgrade from Lenny to Squeeze will go smoothly. A few bugs +have been discovered and reported in the process +(<a href="http://bugs.debian.org/585410">#585410</a> in nagios3-cgi, +<a href="http://bugs.debian.org/584879">#584879</a> already fixed in +enscript and <a href="http://bugs.debian.org/584861">#584861</a> in +kdebase-workspace-data), and to get a more regular testing going on, I +am working on a script to automate the test.</p> + +<p>The idea is to create a Lenny chroot and use tasksel to install a +Gnome or KDE desktop installation inside the chroot before upgrading +it. To ensure no services are started in the chroot, a policy-rc.d +script is inserted. To make sure tasksel believe it is to install a +desktop on a laptop, the tasksel tests are replaced in the chroot +(only acceptable because this is a throw-away chroot).</p> + +<p>A naive upgrade from Lenny to Squeeze using aptitude dist-upgrade +currently always fail because udev refuses to upgrade with the kernel +in Lenny, so to avoid that problem the file /etc/udev/kernel-upgrade +is created. The bug report +<a href="http://bugs.debian.org/566000">#566000</a> make me suspect +this problem do not trigger in a chroot, but I touch the file anyway +to make sure the upgrade go well. Testing on virtual and real +hardware have failed me because of udev so far, and creating this file +do the trick in such settings anyway. This is a +<a href="http://www.linuxquestions.org/questions/debian-26/failed-dist-upgrade-due-to-udev-config_sysfs_deprecated-nonsense-804130/">known +issue</a> and the current udev behaviour is intended by the udev +maintainer because he lack the resources to rewrite udev to keep +working with old kernels or something like that. I really wish the +udev upstream would keep udev backwards compatible, to avoid such +upgrade problem, but given that they fail to do so, I guess +documenting the way out of this mess is the best option we got for +Debian Squeeze.</p> + +<p>Anyway, back to the task at hand, testing upgrades. This test +script, which I call <tt>upgrade-test</tt> for now, is doing the +trick:</p> + +<blockquote><pre> +#!/bin/sh +set -ex + +if [ "$1" ] ; then + desktop=$1 +else + desktop=gnome +fi + +from=lenny +to=squeeze + +exec &lt; /dev/null +unset LANG +mirror=http://ftp.skolelinux.org/debian +tmpdir=chroot-$from-upgrade-$to-$desktop +fuser -mv . +debootstrap $from $tmpdir $mirror +chroot $tmpdir aptitude update +cat > $tmpdir/usr/sbin/policy-rc.d &lt;&lt;EOF +#!/bin/sh +exit 101 +EOF +chmod a+rx $tmpdir/usr/sbin/policy-rc.d +exit_cleanup() { + umount $tmpdir/proc +} +mount -t proc proc $tmpdir/proc +# Make sure proc is unmounted also on failure +trap exit_cleanup EXIT INT + +chroot $tmpdir aptitude -y install debconf-utils + +# Make sure tasksel autoselection trigger. It need the test scripts +# to return the correct answers. +echo tasksel tasksel/desktop multiselect $desktop | \ + chroot $tmpdir debconf-set-selections + +# Include the desktop and laptop task +for test in desktop laptop ; do + echo > $tmpdir/usr/lib/tasksel/tests/$test &lt;&lt;EOF +#!/bin/sh +exit 2 +EOF + chmod a+rx $tmpdir/usr/lib/tasksel/tests/$test +done + +DEBIAN_FRONTEND=noninteractive +DEBIAN_PRIORITY=critical +export DEBIAN_FRONTEND DEBIAN_PRIORITY +chroot $tmpdir tasksel --new-install + +echo deb $mirror $to main > $tmpdir/etc/apt/sources.list +chroot $tmpdir aptitude update +touch $tmpdir/etc/udev/kernel-upgrade +chroot $tmpdir aptitude -y dist-upgrade +fuser -mv +</pre></blockquote> + +<p>I suspect it would be useful to test upgrades with both apt-get and +with aptitude, but I have not had time to look at how they behave +differently so far. I hope to get a cron job running to do the test +regularly and post the result on the web. The Gnome upgrade currently +work, while the KDE upgrade fail because of the bug in +kdebase-workspace-data</p> + +<p>I am not quite sure what kind of extract from the huge upgrade logs +(KDE 167 KiB, Gnome 516 KiB) it make sense to include in this blog +post, so I will refrain from trying. I can report that for Gnome, +aptitude report 760 packages upgraded, 448 newly installed, 129 to +remove and 1 not upgraded and 1024MB need to be downloaded while for +KDE the same numbers are 702 packages upgraded, 507 newly installed, +193 to remove and 0 not upgraded and 1117MB need to be downloaded</p> + +<p>I am very happy to notice that the Gnome desktop + laptop upgrade +is able to migrate to dependency based boot sequencing and parallel +booting without a hitch. Was unsure if there were still bugs with +packages failing to clean up their obsolete init.d script during +upgrades, and no such problem seem to affect the Gnome desktop+laptop +packages.</p> + + + + + Skolelinux er laget for sentraldrifting, naturligvis + http://people.skolelinux.org/pere/blog/Skolelinux_er_laget_for_sentraldrifting__naturligvis.html + http://people.skolelinux.org/pere/blog/Skolelinux_er_laget_for_sentraldrifting__naturligvis.html + Wed, 9 Jun 2010 12:30:00 +0200 + +<p>Det er merkelig hvordan myter om Skolelinux overlever. En slik +myte er at Skolelinux ikke kan sentraldriftes og ha sentralt plasserte +tjenermaskiner. I siste Computerworld Norge er +<a href="http://www.idg.no/computerworld/article169432.ece">IT-sjef +Viggo Billdal i Steinkjer intervjuet</a>, og forteller uten +blygsel:</p> + +<blockquote><p>Vi hadde Skolelinux, men det har vi sluttet med. Vi testet +om det lønte seg med Microsoft eller en åpen plattform. Vi fant ut at +Microsoft egentlig var totalt sett bedre egnet. Det var store +driftskostnader med Skolelinux, blant annet på grunn av +desentraliserte servere. Det var komplisert, så vi gikk vekk fra det +og bruker nå bare Windows.</p></blockquote> + +<p>En <a +href="https://init.linpro.no/pipermail/skolelinux.no/bruker/2010-June/009101.html">rask +sjekk</a> mot den norske brukerlista i Skolelinuxprosjektet forteller +at Steinkjers forsøk foregikk fram til 2004/2005, og at Røysing skole +i Steinkjer skal ha vært svært fornøyd med Skolelinux men at kommunen +overkjørte skolen og krevde at de gikk over til Windows. Et søk på +nettet sendte meg til +<a href="http://www.dn.no/multimedia/archive/00090/Dagens_it_nr__18_90826a.pdf">Dagens +IT nr. 18 2005</a> hvor en kan lese på side 18:</p> + +<blockquote><p>Inge Tømmerås ved Røysing skole i Steinkjer kjører ennå +Microsoft, men forteller at kompetanseutfordringen med Skolelinux ikke +var så stor. ­ Jeg syntes Skolelinux var utrolig lett å drifte uten +forkunnskaper. Men man må jo selvsagt ha tilgang på ekstern kompetanse +til installasjoner og maskinvarefeil, sier Tømmerås.</p></blockquote> + +<p>Som systemarkitekten bak Skolelinux, kan jeg bare riste på hodet +over påstanden om at Skolelinux krever desentraliserte tjenere. +Skolelinux-arkitekturen er laget for sentralisert drift og plassering +av tjenerne lokalt eller sentralt alt etter behov og nettkapasitet. +Den er modellert på nettverks- og tjenerløsningen som brukes på +Universitetet i Tromsø og Oslo, der jeg jobber med utvikling av +driftstjenester. Dette er det heldigvis noen som har fått med seg, og +jeg er glad for å kunne sitere fra en kommentar på den overnevnte +artikkelen. Min venn og gamle kollega Sturle Sunde forteller der: + +<blockquote> +<p>I Flora kommune køyrer vi Skulelinux på skular med alt frå 15 til +meir enn 500 elevar. Dei store skulane har eigen tenar, for det er +mest praktisk. Eg, som er driftsansvarleg for heile nettet, ser +sjeldan dei tenarane fysisk, men at dei står der gjer skulane mindre +avhengige av eksterne linjer som er trege eller dyre. Dei minste +skulane har ikkje eigen tenar. Å bruke sentral tenar er heller ikkje +noko problem. Småskulane klarar seg fint med 1 mbit-linje til ein +sentral tenar eller tenaren på ein større skule.</p> + +<p>Det beste med Skulelinux er halvtjukke klientar. Dei treng ikkje +harddisk og brukar minimalt med ressursar på tenaren fordi dei køyrer +programma lokalt. Eit klasserom med 30 sju-åtte år gamle maskiner har +mykje meir CPU og RAM totalt enn nokon moderne tenar til under +millionen. Det trengst to kommandoar på den sentrale tenaren for å +oppdatere alle klientane, både tynne og halvtjukke. Vi har ingen +problem med diskar som ryk heller, som var eit problem før fordi +elevane sat og sparka i maskinene. Og dei krev lite bandbreidde i +nettet, so det er fullt mogleg å køyre slike på småskular med trege +linjer mot tenaren på ein større skule.</p> + +<p>Flora kommune har nesten 800 Linux-maskiner i sitt skulenett, og +ein person som tek seg av drift av heile nettet, inkludert tenarar, +klientar, operativsystem, programvare, heimekontorløysing og +administrasjon av brukarar.</p> + +<p>No skal det seiast at vi ikkje køyrer rein Skulelinux ut av +boksen. Vi har gjort ein del tilpassingar mot noko Novell-greier som +var der frå før, og som har komplisert installasjonen vår. Etter at +oppsettet var gjort har løysinga vore stabil og kravd minimalt med +arbeid.</p> +</blockquote> + +<p>Jeg vet at Narvik, Harstad og Oslo er kommuner der Skolelinux +sentraldriftes med sentrale tjenere. Det forteller meg at Steinkjers +IT-sjef neppe bør skylde på Skolelinux-løsningen for sine 5 år gamle +minner.</p> + + + + + Upstart or sysvinit - as init.d scripts see it + http://people.skolelinux.org/pere/blog/Upstart_or_sysvinit___as_init_d_scripts_see_it.html + http://people.skolelinux.org/pere/blog/Upstart_or_sysvinit___as_init_d_scripts_see_it.html + Sun, 6 Jun 2010 23:55:00 +0200 + +<p>If Debian is to migrate to upstart on Linux, I expect some init.d +scripts to migrate (some of) their operations to upstart job while +keeping the init.d for hurd and kfreebsd. The packages with such +needs will need a way to get their init.d scripts to behave +differently when used with sysvinit and with upstart. Because of +this, I had a look at the environment variables set when a init.d +script is running under upstart, and when it is not.</p> + +<p>With upstart, I notice these environment variables are set when a +script is started from rcS.d/ (ignoring some irrelevant ones like +COLUMNS):</p> + +<blockquote><pre> +DEFAULT_RUNLEVEL=2 +previous=N +PREVLEVEL= +RUNLEVEL= +runlevel=S +UPSTART_EVENTS=startup +UPSTART_INSTANCE= +UPSTART_JOB=rc-sysinit +</pre></blockquote> + +<p>With sysvinit, these environment variables are set for the same +script.</p> + +<blockquote><pre> +INIT_VERSION=sysvinit-2.88 +previous=N +PREVLEVEL=N +RUNLEVEL=S +runlevel=S +</pre></blockquote> + +<p>The RUNLEVEL and PREVLEVEL environment variables passed on from +sysvinit are not set by upstart. Not sure if it is intentional or not +to not be compatible with sysvinit in this regard.</p> + +<p>For scripts needing to behave differently when upstart is used, +looking for the UPSTART_JOB environment variable seem to be a good +choice.</p> + + + + + A manual for standards wars... + http://people.skolelinux.org/pere/blog/A_manual_for_standards_wars___.html + http://people.skolelinux.org/pere/blog/A_manual_for_standards_wars___.html + Sun, 6 Jun 2010 14:15:00 +0200 + +<p>Via the +<a href="http://feedproxy.google.com/~r/robweir/antic-atom/~3/QzU4RgoAGMg/weekly-links-10.html">blog +of Rob Weir</a> I came across the very interesting essay named +<a href="http://faculty.haas.berkeley.edu/shapiro/wars.pdf">The Art of +Standards Wars</a> (PDF 25 pages). I recommend it for everyone +following the standards wars of today.</p> + + + + + Sitesummary tip: Listing computer hardware models used at site + http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_computer_hardware_models_used_at_site.html + http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_computer_hardware_models_used_at_site.html + Thu, 3 Jun 2010 12:05:00 +0200 + +<p>When using sitesummary at a site to track machines, it is possible +to get a list of the machine types in use thanks to the DMI +information extracted from each machine. The script to do so is +included in the sitesummary package, and here is example output from +the Skolelinux build servers:</p> + +<blockquote><pre> +maintainer:~# /usr/lib/sitesummary/hardware-model-summary + vendor count + Dell Computer Corporation 1 + PowerEdge 1750 1 + IBM 1 + eserver xSeries 345 -[8670M1X]- 1 + Intel 2 + [no-dmi-info] 3 +maintainer:~# +</pre></blockquote> + +<p>The quality of the report depend on the quality of the DMI tables +provided in each machine. Here there are Intel machines without model +information listed with Intel as vendor and mo model, and virtual Xen +machines listed as [no-dmi-info]. One can add -l as a command line +option to list the individual machines.</p> + +<p>A larger list is +<a href="http://narvikskolen.no/sitesummary/">available from the the +city of Narvik</a>, which uses Skolelinux on all their shools and also +provide the basic sitesummary report publicly. In their report there +are ~1400 machines. I know they use both Ubuntu and Skolelinux on +their machines, and as sitesummary is available in both distributions, +it is trivial to get all of them to report to the same central +collector.</p> + + + Togsatsing på norsk, mot sykkel http://people.skolelinux.org/pere/blog/Togsatsing_p___norsk__mot_sykkel.html @@ -215,219 +535,5 @@ ser jeg mye korrespondanse mellom påtrykk og magnetstripe.</p> - - Pieces of the roaming laptop puzzle in Debian - http://people.skolelinux.org/pere/blog/Pieces_of_the_roaming_laptop_puzzle_in_Debian.html - http://people.skolelinux.org/pere/blog/Pieces_of_the_roaming_laptop_puzzle_in_Debian.html - Wed, 19 May 2010 19:00:00 +0200 - -<p>Today, the last piece of the puzzle for roaming laptops in Debian -Edu finally entered the Debian archive. Today, the new -<a href="http://packages.qa.debian.org/libp/libpam-mklocaluser.html">libpam-mklocaluser</a> -package was accepted. Two days ago, two other pieces was accepted -into unstable. The -<a href="http://packages.qa.debian.org/p/pam-python.html">pam-python</a> -package needed by libpam-mklocaluser, and the -<a href="http://packages.qa.debian.org/s/sssd.html">sssd</a> package -passed NEW on Monday. In addition, the -<a href="http://packages.qa.debian.org/libp/libpam-ccreds.html">libpam-ccreds</a> -package we need is in experimental (version 10-4) since Saturday, and -hopefully will be moved to unstable soon.</p> - -<p>This collection of packages allow for two different setups for -roaming laptops. The traditional setup would be using libpam-ccreds, -nscd and libpam-mklocaluser with LDAP or Kerberos authentication, -which should work out of the box if the configuration changes proposed -for nscd in <a href="http://bugs.debian.org/485282">BTS report -#485282</a> is implemented. The alternative setup is to use sssd with -libpam-mklocaluser to connect to LDAP or Kerberos and let sssd take -care of the caching of passwords and group information.</p> - -<p>I have so far been unable to get sssd to work with the LDAP server -at the University, but suspect the issue is some SSL/GnuTLS related -problem with the server certificate. I plan to update the Debian -package to version 1.2, which is scheduled for next week, and hope to -find time to make sure the next release will include both the -Debian/Ubuntu specific patches. Upstream is friendly and responsive, -and I am sure we will find a good solution.</p> - -<p>The idea is to set up the roaming laptops to authenticate using -LDAP or Kerberos and create a local user with home directory in /home/ -when a usre in LDAP logs in via KDM or GDM for the first time, and -cache the password for offline checking, as well as caching group -memberhips and other relevant LDAP information. The -libpam-mklocaluser package was created to make sure the local home -directory is in /home/, instead of /site/server/directory/ which would -be the home directory if pam_mkhomedir was used. To avoid confusion -with support requests and configuration, we do not want local laptops -to have users in a path that is used for the same users home directory -on the home directory servers.</p> - -<p>One annoying problem with gdm is that it do not show the PAM -message passed to the user from libpam-mklocaluser when the local user -is created. Instead gdm simply reject the login with some generic -message. The message is shown in kdm, ssh and login, so I guess it is -a bug in gdm. Have not investigated if there is some other message -type that can be used instead to get gdm to also show the message.</p> - -<p>If you want to help out with implementing this for Debian Edu, -please contact us on debian-edu@lists.debian.org.</p> - - - - - Parallellized boot is now the default in Debian/unstable - http://people.skolelinux.org/pere/blog/Parallellized_boot_is_now_the_default_in_Debian_unstable.html - http://people.skolelinux.org/pere/blog/Parallellized_boot_is_now_the_default_in_Debian_unstable.html - Fri, 14 May 2010 22:40:00 +0200 - -<p>Since this evening, parallel booting is the default in -Debian/unstable for machines using dependency based boot sequencing. -Apparently the testing of concurrent booting has been wider than -expected, if I am to believe the -<a href="http://lists.debian.org/debian-devel/2010/05/msg00122.html">input -on debian-devel@</a>, and I concluded a few days ago to move forward -with the feature this weekend, to give us some time to detect any -remaining problems before Squeeze is frozen. If serious problems are -detected, it is simple to change the default back to sequential boot. -The upload of the new sysvinit package also activate a new upstream -version.</p> - -More information about -<a href="http://wiki.debian.org/LSBInitScripts/DependencyBasedBoot">dependency -based boot sequencing</a> is available from the Debian wiki. It is -currently possible to disable parallel booting when one run into -problems caused by it, by adding this line to /etc/default/rcS:</p> - -<blockquote><pre> -CONCURRENCY=none -</pre></blockquote> - -<p>If you report any problems with dependencies in init.d scripts to -the BTS, please usertag the report to get it to show up at -<a href="http://bugs.debian.org/cgi-bin/pkgreport.cgi?users=initscripts-ng-devel@lists.alioth.debian.org">the -list of usertagged bugs related to this</a>.</p> - - - - - Sitesummary tip: Listing MAC address of all clients - http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_MAC_address_of_all_clients.html - http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_MAC_address_of_all_clients.html - Fri, 14 May 2010 21:10:00 +0200 - -<p>In the recent Debian Edu versions, the -<a href="http://wiki.debian.org/DebianEdu/HowTo/SiteSummary">sitesummary -system</a> is used to keep track of the machines in the school -network. Each machine will automatically report its status to the -central server after boot and once per night. The network setup is -also reported, and using this information it is possible to get the -MAC address of all network interfaces in the machines. This is useful -to update the DHCP configuration.</p> - -<p>To give some idea how to use sitesummary, here is a one-liner to -ist all MAC addresses of all machines reporting to sitesummary. Run -this on the collector host:</p> - -<blockquote><pre> -perl -MSiteSummary -e 'for_all_hosts(sub { print join(" ", get_macaddresses(shift)), "\n"; });' -</pre></blockquote> - -<p>This will list all MAC addresses assosiated with all machine, one -line per machine and with space between the MAC addresses.</p> - -<p>To allow system administrators easier job at adding static DHCP -addresses for hosts, it would be possible to extend this to fetch -machine information from sitesummary and update the DHCP and DNS -tables in LDAP using this information. Such tool is unfortunately not -written yet.</p> - - - - - systemd, an interesting alternative to upstart - http://people.skolelinux.org/pere/blog/systemd__an_interesting_alternative_to_upstart.html - http://people.skolelinux.org/pere/blog/systemd__an_interesting_alternative_to_upstart.html - Thu, 13 May 2010 22:20:00 +0200 - -<p>The last few days a new boot system called -<a href="http://www.freedesktop.org/wiki/Software/systemd">systemd</a> -has been -<a href="http://0pointer.de/blog/projects/systemd.html">introduced</a> - -to the free software world. I have not yet had time to play around -with it, but it seem to be a very interesting alternative to -<a href="http://upstart.ubuntu.com/">upstart</a>, and might prove to be -a good alternative for Debian when we are able to switch to an event -based boot system. Tollef is -<a href="http://bugs.debian.org/580814">in the process</a> of getting -systemd into Debian, and I look forward to seeing how well it work. I -like the fact that systemd handles init.d scripts with dependency -information natively, allowing them to run in parallel where upstart -at the moment do not.</p> - -<p>Unfortunately do systemd have the same problem as upstart regarding -platform support. It only work on recent Linux kernels, and also need -some new kernel features enabled to function properly. This means -kFreeBSD and Hurd ports of Debian will need a port or a different boot -system. Not sure how that will be handled if systemd proves to be the -way forward.</p> - -<p>In the mean time, based on the -<a href="http://lists.debian.org/debian-devel/2010/05/msg00122.html">input -on debian-devel@</a> regarding parallel booting in Debian, I have -decided to enable full parallel booting as the default in Debian as -soon as possible (probably this weekend or early next week), to see if -there are any remaining serious bugs in the init.d dependencies. A -new version of the sysvinit package implementing this change is -already in experimental. If all go well, Squeeze will be released -with parallel booting enabled by default.</p> - - - - - Parallellizing the boot in Debian Squeeze - ready for wider testing - http://people.skolelinux.org/pere/blog/Parallellizing_the_boot_in_Debian_Squeeze___ready_for_wider_testing.html - http://people.skolelinux.org/pere/blog/Parallellizing_the_boot_in_Debian_Squeeze___ready_for_wider_testing.html - Thu, 6 May 2010 23:25:00 +0200 - -<p>These days, the init.d script dependencies in Squeeze are quite -complete, so complete that it is actually possible to run all the -init.d scripts in parallell based on these dependencies. If you want -to test your Squeeze system, make sure -<a href="http://wiki.debian.org/LSBInitScripts/DependencyBasedBoot">dependency -based boot sequencing</a> is enabled, and add this line to -/etc/default/rcS:</p> - -<blockquote><pre> -CONCURRENCY=makefile -</pre></blockquote> - -<p>That is it. It will cause sysv-rc to use the startpar tool to run -scripts in parallel using the dependency information stored in -/etc/init.d/.depend.boot, /etc/init.d/.depend.start and -/etc/init.d/.depend.stop to order the scripts. Startpar is configured -to try to start the kdm and gdm scripts as early as possible, and will -start the facilities required by kdm or gdm as early as possible to -make this happen.</p> - -<p>Give it a try, and see if you like the result. If some services -fail to start properly, it is most likely because they have incomplete -init.d script dependencies in their startup script (or some of their -dependent scripts have incomplete dependencies). Report bugs and get -the package maintainers to fix it. :)</p> - -<p>Running scripts in parallel could be the default in Debian when we -manage to get the init.d script dependencies complete and correct. I -expect we will get there in Squeeze+1, if we get manage to test and -fix the remaining issues.</p> - -<p>If you report any problems with dependencies in init.d scripts to -the BTS, please usertag the report to get it to show up at -<a href="http://bugs.debian.org/cgi-bin/pkgreport.cgi?users=initscripts-ng-devel@lists.alioth.debian.org">the -list of usertagged bugs related to this</a>.</p> - - -