Petter Reinholdtsen

Entries from June 2010.

LUMA, a very nice LDAP GUI
28th June 2010

The last few days I have been looking into the status of the LDAP directory in Debian Edu, and in the process I started to miss a GUI tool to browse the LDAP tree. The only one I was able to find in Debian/Squeeze and Lenny is LUMA, which has proved to be a great tool to get a overview of the current LDAP directory populated by default in Skolelinux. Thanks to it, I have been able to find empty and obsolete subtrees, misplaced objects and duplicate objects. It will be installed by default in Debian/Squeeze. If you are working with LDAP, give it a go. :)

I did notice one problem with it I have not had time to report to the BTS yet. There is no .desktop file in the package, so the tool do not show up in the Gnome and KDE menus, but only deep down in in the Debian submenu in KDE. I hope that can be fixed before Squeeze is released.

I have not yet been able to get it to modify the tree yet. I would like to move objects and remove subtrees directly in the GUI, but have not found a way to do that with LUMA yet. So in the mean time, I use ldapvi for that.

If you have tips on other GUI tools for LDAP that might be useful in Debian Edu, please contact us on

Update 2010-06-29: Ross Reedstrom tipped us about the gq package as a useful GUI alternative. It seem like a good tool, but is unmaintained in Debian and got a RC bug keeping it out of Squeeze. Unless that changes, it will not be an option for Debian Edu based on Squeeze.

Tags: debian, debian edu, english, ldap, nuug.
Idea for a change to LDAP schemas allowing DNS and DHCP info to be combined into one object
24th June 2010

A while back, I complained about the fact that it is not possible with the provided schemas for storing DNS and DHCP information in LDAP to combine the two sets of information into one LDAP object representing a computer.

In the mean time, I discovered that a simple fix would be to make the dhcpHost object class auxiliary, to allow it to be combined with the dNSDomain object class, and thus forming one object for one computer when storing both DHCP and DNS information in LDAP.

If I understand this correctly, it is not safe to do this change without also changing the assigned number for the object class, and I do not know enough about LDAP schema design to do that properly for Debian Edu.

Anyway, for future reference, this is how I believe we could change the DHCP schema to solve at least part of the problem with the LDAP schemas available today from IETF.

--- dhcp.schema    (revision 65192)
+++ dhcp.schema    (working copy)
@@ -376,7 +376,7 @@
 objectclass ( 2.16.840.1.113719.
        NAME 'dhcpHost'
        DESC 'This represents information about a particular client'
-       SUP top
+       SUP top AUXILIARY
        MUST cn
        MAY  (dhcpLeaseDN $ dhcpHWAddress $ dhcpOptionsDN $ dhcpStatements $ dhcpComments $ dhcpOption)
        X-NDS_CONTAINMENT ('dhcpService' 'dhcpSubnet' 'dhcpGroup') )

I very much welcome clues on how to do this properly for Debian Edu/Squeeze. We provide the DHCP schema in our debian-edu-config package, and should thus be free to rewrite it as we see fit.

If you want to help out with implementing this for Debian Edu, please contact us on

Tags: debian, debian edu, english, ldap, nuug.
Calling tasksel like the installer, while still getting useful output
16th June 2010

A few times I have had the need to simulate the way tasksel installs packages during the normal debian-installer run. Until now, I have ended up letting tasksel do the work, with the annoying problem of not getting any feedback at all when something fails (like a conffile question from dpkg or a download that fails), using code like this:

export DEBIAN_FRONTEND=noninteractive
tasksel --new-install
This would invoke tasksel, let its automatic task selection pick the tasks to install, and continue to install the requested tasks without any output what so ever. Recently I revisited this problem while working on the automatic package upgrade testing, because tasksel would some times hang without any useful feedback, and I want to see what is going on when it happen. Then it occured to me, I can parse the output from tasksel when asked to run in test mode, and use that aptitude command line printed by tasksel then to simulate the tasksel run. I ended up using code like this:
export DEBIAN_FRONTEND=noninteractive
cmd="$(in_target tasksel -t --new-install | sed 's/debconf-apt-progress -- //')"

The content of $cmd is typically something like "aptitude -q --without-recommends -o APT::Install-Recommends=no -y install ~t^desktop$ ~t^gnome-desktop$ ~t^laptop$ ~pstandard ~prequired ~pimportant", which will install the gnome desktop task, the laptop task and all packages with priority standard , required and important, just like tasksel would have done it during installation.

A better approach is probably to extend tasksel to be able to install packages without using debconf-apt-progress, for use cases like this.

Tags: debian, english, nuug.
Vinmonopolet bryter loven åpenlyst - og flere planlegger å gjøre det samme
16th June 2010

Dagbladet melder at Vinmonopolet med bakgrunn i vekterstreiken som pågår i Norge for tiden, har bestemt seg for med vitende og vilje å bryte sentralbanklovens paragraf 14 ved å nekte folk å betale med kontanter, og at flere butikker planlegger å følge deres eksempel. Jeg synes det er hårreisende hvis de slipper unna med et slikt soleklart lovbrudd, og lurer på hva slags muligheter jeg vil ha hvis jeg blir nektet å handle med kontanter. Jeg handler i hovedsak med kontanter selv, da jeg anser det som en borgerrett å kunne handle anonymt uten at det blir registrert. For meg er det et angrep på mitt personvern å nekte å ta imot kontant betaling.

Paragrafen i sentralbankloven lyder:

§ 14. Tvungent betalingsmiddel

Bankens sedler og mynter er tvungent betalingsmiddel i Norge. Ingen er pliktig til i én betaling å ta imot mer enn femogtyve mynter av hver enhet.

Sterkt skadde sedler og mynter er ikke tvungent betalingsmiddel. Banken gir nærmere forskrifter om erstatning for bortkomne, brente eller skadde sedler og mynter.

Selv om en avtale inneholder klausul om betaling av en pengeforpliktelse i gullverdi, kan skyldneren frigjøre seg med tvungne betalingsmidler uten hensyn til denne klausul.

Det er med bakgrunn i denne lovet ikke tillatt å nekte å ta imot kontakt betaling. Det er en lov jeg har sans for, og som jeg mener må håndheves strengt.

Tags: norsk, personvern.
Officeshots taking shape
13th June 2010

For those of us caring about document exchange and interoperability, OfficeShots is a great service. It is to ODF documents what BrowserShots is for web pages.

A while back, I was contacted by Knut Yrvin at the part of Nokia that used to be Trolltech, who wanted to help the OfficeShots project and wondered if the University of Oslo where I work would be interested in supporting the project. I helped him to navigate his request to the right people at work, and his request was answered with a spot in the machine room with power and network connected, and Knut arranged funding for a machine to fill the spot. The machine is administrated by the OfficeShots people, so I do not have daily contact with its progress, and thus from time to time check back to see how the project is doing.

Today I had a look, and was happy to see that the Dell box in our machine room now is the host for several virtual machines running as OfficeShots factories, and the project is able to render ODF documents in 17 different document processing implementation on Linux and Windows. This is great.

Tags: english, standard.
Lenny->Squeeze upgrades, removals by apt and aptitude
13th June 2010

My testing of Debian upgrades from Lenny to Squeeze continues, and I've finally made the upgrade logs available from I am now testing dist-upgrade of Gnome and KDE in a chroot using both apt and aptitude, and found their differences interesting. This time I will only focus on their removal plans.

After installing a Gnome desktop and the laptop task, apt-get wants to remove 72 packages when dist-upgrading from Lenny to Squeeze. The surprising part is that it want to remove xorg and all xserver-xorg-video* drivers. Clearly not a good choice, but I am not sure why. When asking aptitude to do the same, it want to remove 129 packages, but most of them are library packages I suspect are no longer needed. Both of them want to remove bluetooth packages, which I do not know. Perhaps these bluetooth packages are obsolete?

For KDE, apt-get want to remove 82 packages, among them kdebase which seem like a bad idea and xorg the same way as with Gnome. Asking aptitude for the same, it wants to remove 192 packages, none which are too surprising.

I guess the removal of xorg during upgrades should be investigated and avoided, and perhaps others as well. Here are the complete list of planned removals. The complete logs is available from the URL above. Note if you want to repeat these tests, that the upgrade test for kde+apt-get hung in the tasksel setup because of dpkg asking conffile questions. No idea why. I worked around it by using 'echo >> /proc/pidofdpkg/fd/0' to tell dpkg to continue.

apt-get gnome 72
bluez-gnome cupsddk-drivers deskbar-applet gnome gnome-desktop-environment gnome-network-admin gtkhtml3.14 iceweasel-gnome-support libavcodec51 libdatrie0 libgdl-1-0 libgnomekbd2 libgnomekbdui2 libmetacity0 libslab0 libxcb-xlib0 nautilus-cd-burner python-gnome2-desktop python-gnome2-extras serpentine swfdec-mozilla update-manager xorg xserver-xorg xserver-xorg-core xserver-xorg-input-all xserver-xorg-input-evdev xserver-xorg-input-kbd xserver-xorg-input-mouse xserver-xorg-input-synaptics xserver-xorg-input-wacom xserver-xorg-video-all xserver-xorg-video-apm xserver-xorg-video-ark xserver-xorg-video-ati xserver-xorg-video-chips xserver-xorg-video-cirrus xserver-xorg-video-cyrix xserver-xorg-video-dummy xserver-xorg-video-fbdev xserver-xorg-video-glint xserver-xorg-video-i128 xserver-xorg-video-i740 xserver-xorg-video-imstt xserver-xorg-video-intel xserver-xorg-video-mach64 xserver-xorg-video-mga xserver-xorg-video-neomagic xserver-xorg-video-nsc xserver-xorg-video-nv xserver-xorg-video-openchrome xserver-xorg-video-r128 xserver-xorg-video-radeon xserver-xorg-video-radeonhd xserver-xorg-video-rendition xserver-xorg-video-s3 xserver-xorg-video-s3virge xserver-xorg-video-savage xserver-xorg-video-siliconmotion xserver-xorg-video-sis xserver-xorg-video-sisusb xserver-xorg-video-tdfx xserver-xorg-video-tga xserver-xorg-video-trident xserver-xorg-video-tseng xserver-xorg-video-v4l xserver-xorg-video-vesa xserver-xorg-video-vga xserver-xorg-video-vmware xserver-xorg-video-voodoo xulrunner-1.9 xulrunner-1.9-gnome-support

aptitude gnome 129
bluez-gnome bluez-utils cpp-4.3 cupsddk-drivers dhcdbd djvulibre-desktop finger gnome-app-install gnome-mount gnome-network-admin gnome-spell gnome-vfs-obexftp gnome-volume-manager gstreamer0.10-gnomevfs gtkhtml3.14 libao2 libavahi-compat-libdnssd1 libavahi-core5 libavcodec51 libbluetooth2 libcamel1.2-11 libcdio7 libcucul0 libcupsys2 libcurl3 libdatrie0 libdirectfb-1.0-0 libdvdread3 libedataserver1.2-9 libeel2-2.20 libeel2-data libepc-1.0-1 libepc-ui-1.0-1 libfaad0 libgail-common libgd2-noxpm libgda3-3 libgda3-common libgdl-1-0 libgdl-1-common libggz2 libggzcore9 libggzmod4 libgksu1.2-0 libgksuui1.0-1 libgmyth0 libgnomecups1.0-1 libgnomekbd2 libgnomekbdui2 libgnomeprint2.2-0 libgnomeprint2.2-data libgnomeprintui2.2-0 libgnomeprintui2.2-common libgnomevfs2-bin libgpod3 libgraphviz4 libgtkhtml2-0 libgtksourceview-common libgtksourceview1.0-0 libgucharmap6 libhesiod0 libicu38 libiw29 libkpathsea4 libltdl3 libmagick++10 libmagick10 libmalaga7 libmetacity0 libmtp7 libmysqlclient15off libnautilus-burn4 libneon27 libnm-glib0 libnm-util0 libopal-2.2 libosp5 libparted1.8-10 libpoppler-glib3 libpoppler3 libpt-1.10.10 libpt-1.10.10-plugins-alsa libpt-1.10.10-plugins-v4l libraw1394-8 libsensors3 libslab0 libsmbios2 libsoup2.2-8 libssh2-1 libsuitesparse-3.1.0 libswfdec-0.6-90 libtalloc1 libtotem-plparser10 libtrackerclient0 libxalan2-java libxalan2-java-gcj libxcb-xlib0 libxerces2-java libxerces2-java-gcj libxklavier12 libxtrap6 libxxf86misc1 libzephyr3 mysql-common nautilus-cd-burner openssl-blacklist p7zip python-4suite-xml python-eggtrayicon python-gnome2-desktop python-gnome2-extras python-gtkhtml2 python-gtkmozembed python-numeric python-sexy serpentine svgalibg1 swfdec-gnome swfdec-mozilla totem-gstreamer update-manager wodim xserver-xorg-video-cyrix xserver-xorg-video-imstt xserver-xorg-video-nsc xserver-xorg-video-v4l xserver-xorg-video-vga zip

apt-get kde 82
cupsddk-drivers karm kaudiocreator kcoloredit kcontrol kde kde-core kdeaddons kdeartwork kdebase kdebase-bin kdebase-bin-kde3 kdebase-kio-plugins kdesktop kdeutils khelpcenter kicker kicker-applets knewsticker kolourpaint konq-plugins konqueror korn kpersonalizer kscreensaver ksplash libavcodec51 libdatrie0 libkiten1 libxcb-xlib0 quanta superkaramba texlive-base-bin xorg xserver-xorg xserver-xorg-core xserver-xorg-input-all xserver-xorg-input-evdev xserver-xorg-input-kbd xserver-xorg-input-mouse xserver-xorg-input-synaptics xserver-xorg-input-wacom xserver-xorg-video-all xserver-xorg-video-apm xserver-xorg-video-ark xserver-xorg-video-ati xserver-xorg-video-chips xserver-xorg-video-cirrus xserver-xorg-video-cyrix xserver-xorg-video-dummy xserver-xorg-video-fbdev xserver-xorg-video-glint xserver-xorg-video-i128 xserver-xorg-video-i740 xserver-xorg-video-imstt xserver-xorg-video-intel xserver-xorg-video-mach64 xserver-xorg-video-mga xserver-xorg-video-neomagic xserver-xorg-video-nsc xserver-xorg-video-nv xserver-xorg-video-openchrome xserver-xorg-video-r128 xserver-xorg-video-radeon xserver-xorg-video-radeonhd xserver-xorg-video-rendition xserver-xorg-video-s3 xserver-xorg-video-s3virge xserver-xorg-video-savage xserver-xorg-video-siliconmotion xserver-xorg-video-sis xserver-xorg-video-sisusb xserver-xorg-video-tdfx xserver-xorg-video-tga xserver-xorg-video-trident xserver-xorg-video-tseng xserver-xorg-video-v4l xserver-xorg-video-vesa xserver-xorg-video-vga xserver-xorg-video-vmware xserver-xorg-video-voodoo xulrunner-1.9

aptitude kde 192
bluez-utils cpp-4.3 cupsddk-drivers cvs dcoprss dhcdbd djvulibre-desktop dosfstools eyesapplet fifteenapplet finger gettext ghostscript-x imlib-base imlib11 indi kandy karm kasteroids kaudiocreator kbackgammon kbstate kcoloredit kcontrol kcron kdat kdeadmin-kfile-plugins kdeartwork-misc kdeartwork-theme-window kdebase-bin-kde3 kdebase-kio-plugins kdeedu-data kdegraphics-kfile-plugins kdelirc kdemultimedia-kappfinder-data kdemultimedia-kfile-plugins kdenetwork-kfile-plugins kdepim-kfile-plugins kdepim-kio-plugins kdeprint kdesktop kdessh kdict kdnssd kdvi kedit keduca kenolaba kfax kfaxview kfouleggs kghostview khelpcenter khexedit kiconedit kitchensync klatin klickety kmailcvt kmenuedit kmid kmilo kmoon kmrml kodo kolourpaint kooka korn kpager kpdf kpercentage kpf kpilot kpoker kpovmodeler krec kregexpeditor ksayit ksim ksirc ksirtet ksmiletris ksmserver ksnake ksokoban ksplash ksvg ksysv ktip ktnef kuickshow kverbos kview kviewshell kvoctrain kwifimanager kwin kwin4 kworldclock kxsldbg libakode2 libao2 libarts1-akode libarts1-audiofile libarts1-mpeglib libarts1-xine libavahi-compat-libdnssd1 libavahi-core5 libavc1394-0 libavcodec51 libbluetooth2 libboost-python1.34.1 libcucul0 libcurl3 libcvsservice0 libdatrie0 libdirectfb-1.0-0 libdjvulibre21 libdvdread3 libfaad0 libfreebob0 libgail-common libgd2-noxpm libgraphviz4 libgsmme1c2a libgtkhtml2-0 libicu38 libiec61883-0 libindex0 libiw29 libk3b3 libkcal2b libkcddb1 libkdeedu3 libkdepim1a libkgantt0 libkiten1 libkleopatra1 libkmime2 libkpathsea4 libkpimexchange1 libkpimidentities1 libkscan1 libksieve0 libktnef1 liblockdev1 libltdl3 libmagick10 libmimelib1c2a libmozjs1d libmpcdec3 libneon27 libnm-util0 libopensync0 libpisock9 libpoppler-glib3 libpoppler-qt2 libpoppler3 libraw1394-8 libsmbios2 libssh2-1 libsuitesparse-3.1.0 libtalloc1 libtiff-tools libxalan2-java libxalan2-java-gcj libxcb-xlib0 libxerces2-java libxerces2-java-gcj libxtrap6 mpeglib networkstatus pmount poster psutils quanta quanta-data superkaramba svgalibg1 tex-common texlive-base texlive-base-bin texlive-common texlive-doc-base texlive-fonts-recommended xserver-xorg-video-cyrix xserver-xorg-video-imstt xserver-xorg-video-nsc xserver-xorg-video-v4l xserver-xorg-video-vga xulrunner-1.9

Tags: debian, debian edu, english.
Åpne trådløsnett er et samfunnsgode
12th June 2010

Veldig glad for å oppdage via Slashdot at folk i Finland har forstått at åpne trådløsnett er et samfunnsgode. Jeg ser på åpne trådløsnett som et fellesgode på linje med retten til ferdsel i utmark og retten til å bevege seg i strandsonen. Jeg har glede av åpne trådløsnett når jeg finner dem, og deler gladelig nett med andre så lenge de ikke forstyrrer min bruk av eget nett. Nettkapasiteten er sjelden en begrensning ved normal browsing og enkel SSH-innlogging (som er min vanligste nettbruk), og nett kan brukes til så mye positivt og nyttig (som nyhetslesing, sjekke været, kontakte slekt og venner, holde seg oppdatert om politiske saker, kontakte organisasjoner og politikere, etc), at det for meg er helt urimelig å blokkere dette for alle som ikke gjør en flue fortred. De som mener at potensialet for misbruk er grunn nok til å hindre all den positive og lovlydige bruken av et åpent trådløsnett har jeg dermed ingen forståelse for. En kan ikke la eksistensen av forbrytere styre hvordan samfunnet skal organiseres. Da får en et kontrollsamfunn de færreste ønsker å leve i, og det at vi har et samfunn i Norge der tilliten til hverandre er høy gjør at samfunnet fungerer ganske godt. Det bør vi anstrenge oss for å beholde.

Tags: fildeling, norsk, nuug, opphavsrett, personvern, sikkerhet.
Automatic upgrade testing from Lenny to Squeeze
11th June 2010

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 (#585410 in nagios3-cgi, #584879 already fixed in enscript and #584861 in kdebase-workspace-data), and to get a more regular testing going on, I am working on a script to automate the test.

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).

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 #566000 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 known issue 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.

Anyway, back to the task at hand, testing upgrades. This test script, which I call upgrade-test for now, is doing the trick:

set -ex

if [ "$1" ] ; then


exec < /dev/null
unset LANG
fuser -mv .
debootstrap $from $tmpdir $mirror
chroot $tmpdir aptitude update
cat > $tmpdir/usr/sbin/policy-rc.d <<EOF
exit 101
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 <<EOF
exit 2
    chmod a+rx $tmpdir/usr/lib/tasksel/tests/$test

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

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

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

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.

Tags: bootsystem, debian, debian edu, english.
Skolelinux er laget for sentraldrifting, naturligvis
9th June 2010

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 IT-sjef Viggo Billdal i Steinkjer intervjuet, og forteller uten blygsel:

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.

En rask sjekk 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 Dagens IT nr. 18 2005 hvor en kan lese på side 18:

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.

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:

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.

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.

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.

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.

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.

Tags: debian edu, norsk, nuug.
Upstart or sysvinit - as init.d scripts see it
6th June 2010

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.

With upstart, I notice these environment variables are set when a script is started from rcS.d/ (ignoring some irrelevant ones like COLUMNS):


With sysvinit, these environment variables are set for the same script.


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.

For scripts needing to behave differently when upstart is used, looking for the UPSTART_JOB environment variable seem to be a good choice.

Tags: bootsystem, debian, english.
A manual for standards wars...
6th June 2010

Via the blog of Rob Weir I came across the very interesting essay named The Art of Standards Wars (PDF 25 pages). I recommend it for everyone following the standards wars of today.

Tags: debian, debian edu, english, standard.
Sitesummary tip: Listing computer hardware models used at site
3rd June 2010

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:

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

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 no model, and virtual Xen machines listed as [no-dmi-info]. One can add -l as a command line option to list the individual machines.

A larger list is available from the the city of Narvik, 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.

Tags: debian, debian edu, english, sitesummary.
Togsatsing på norsk, mot sykkel
2nd June 2010

Det står dårlig til med toget når en finner på å la det kappkjøre med sykkel... Jeg tror det trengs strukturendringer for å få fikset på togproblemene i Norge.

Mon tro hva toglinje mellom Narvik og Tromsø ville hatt slags effekt på området der?

Tags: norsk.
KDM fail at boot with NVidia cards - and no one try to fix it?
1st June 2010

It is strange to watch how a bug in Debian causing KDM to fail to start at boot when an NVidia video card is used is handled. The problem seem to be that the nvidia driver uses a long time to initialize, and this duration is longer than kdm is configured to wait.

I came across two bugs related to this issue, #583312 initially filed against initscripts and passed on to nvidia-glx when it became obvious that the nvidia drivers were involved, and #524751 initially filed against kdm and passed on to src:nvidia-graphics-drivers for unknown reasons.

To me, it seem that no-one is interested in actually solving the problem nvidia video card owners experience and make sure the Debian distribution work out of the box for these users. The nvidia driver maintainers expect kdm to be set up to wait longer, while kdm expect the nvidia driver maintainers to fix the driver to start faster, and while they wait for each other I guess the users end up switching to a distribution that work for them. I have no idea what the solution is, but I am pretty sure that waiting for each other is not it.

I wonder why we end up handling bugs this way.

Tags: bootsystem, debian, debian edu, english.

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