1 <?xml version=
"1.0" encoding=
"utf-8"?>
2 <rss version='
2.0' xmlns:lj='http://www.livejournal.org/rss/lj/
1.0/' xmlns:
atom=
"http://www.w3.org/2005/Atom">
4 <title>Petter Reinholdtsen
</title>
5 <description></description>
6 <link>http://people.skolelinux.org/pere/blog/
</link>
7 <atom:link href=
"http://people.skolelinux.org/pere/blog/index.rss" rel=
"self" type=
"application/rss+xml" />
10 <title>Sitesummary tip: Listing computer hardware models used at site
</title>
11 <link>http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_computer_hardware_models_used_at_site.html
</link>
12 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_computer_hardware_models_used_at_site.html
</guid>
13 <pubDate>Thu,
3 Jun
2010 12:
05:
00 +
0200</pubDate>
15 <p
>When using sitesummary at a site to track machines, it is possible
16 to get a list of the machine types in use thanks to the DMI
17 information extracted from each machine. The script to do so is
18 included in the sitesummary package, and here is example output from
19 the Skolelinux build servers:
</p
>
21 <blockquote
><pre
>
22 maintainer:~# /usr/lib/sitesummary/hardware-model-summary
24 Dell Computer Corporation
1
27 eserver xSeries
345 -[
8670M1X]-
1
31 </pre
></blockquote
>
33 <p
>The quality of the report depend on the quality of the DMI tables
34 provided in each machine. Here there are Intel machines without model
35 information listed with Intel as vendor and mo model, and virtual Xen
36 machines listed as [no-dmi-info]. One can add -l as a command line
37 option to list the individual machines.
</p
>
39 <p
>A larger list is
40 <a href=
"http://narvikskolen.no/sitesummary/
">available from the the
41 city of Narvik
</a
>, which uses Skolelinux on all their shools and also
42 provide the basic sitesummary report publicly. In their report there
43 are ~
1400 machines. I know they use both Ubuntu and Skolelinux on
44 their machines, and as sitesummary is available in both distributions,
45 it is trivial to get all of them to report to the same central
51 <title>Togsatsing på norsk, mot sykkel
</title>
52 <link>http://people.skolelinux.org/pere/blog/Togsatsing_p___norsk__mot_sykkel.html
</link>
53 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Togsatsing_p___norsk__mot_sykkel.html
</guid>
54 <pubDate>Wed,
2 Jun
2010 23:
45:
00 +
0200</pubDate>
56 <p
>Det står dårlig til med toget når en finner på å la det
57 <a href=
"http://www.aftenposten.no/nyheter/iriks/article3677060.ece
">kappkjøre
58 med sykkel
</a
>... Jeg tror det trengs strukturendringer for å få
59 fikset på togproblemene i Norge.
</p
>
61 <p
>Mon tro hva toglinje mellom Narvik og Tromsø ville hatt slags
62 effekt på området der?
</p
>
67 <title>KDM fail at boot with NVidia cards - and no one try to fix it?
</title>
68 <link>http://people.skolelinux.org/pere/blog/KDM_fail_at_boot_with_NVidia_cards___and_no_one_try_to_fix_it_.html
</link>
69 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/KDM_fail_at_boot_with_NVidia_cards___and_no_one_try_to_fix_it_.html
</guid>
70 <pubDate>Tue,
1 Jun
2010 17:
05:
00 +
0200</pubDate>
72 <p
>It is strange to watch how a bug in Debian causing KDM to fail to
73 start at boot when an NVidia video card is used is handled. The
74 problem seem to be that the nvidia X.org driver uses a long time to
75 initialize, and this duration is longer than kdm is configured to
78 <p
>I came across two bugs related to this issue,
79 <a href=
"http://bugs.debian.org/
583312">#
583312</a
> initially filed
80 against initscripts and passed on to nvidia-glx when it became obvious
81 that the nvidia drivers were involved, and
82 <a href=
"http://bugs.debian.org/
524751">#
524751</a
> initially filed against
83 kdm and passed on to src:nvidia-graphics-drivers for unknown reasons.
</p
>
85 <p
>To me, it seem that no-one is interested in actually solving the
86 problem nvidia video card owners experience and make sure the Debian
87 distribution work out of the box for these users. The nvidia driver
88 maintainers expect kdm to be set up to wait longer, while kdm expect
89 the nvidia driver maintainers to fix the driver to start faster, and
90 while they wait for each other I guess the users end up switching to a
91 distribution that work for them. I have no idea what the solution is,
92 but I am pretty sure that waiting for each other is not it.
</p
>
94 <p
>I wonder why we end up handling bugs this way.
</p
>
99 <title>Parallellized boot seem to hold up well in Debian/testing
</title>
100 <link>http://people.skolelinux.org/pere/blog/Parallellized_boot_seem_to_hold_up_well_in_Debian_testing.html
</link>
101 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Parallellized_boot_seem_to_hold_up_well_in_Debian_testing.html
</guid>
102 <pubDate>Thu,
27 May
2010 23:
55:
00 +
0200</pubDate>
104 <p
>A few days ago, parallel booting was enabled in Debian/testing.
105 The feature seem to hold up pretty well, but three fairly serious
106 issues are known and should be solved:
110 <li
>The wicd package seen to
111 <a href=
"http://bugs.debian.org/
508289">break NFS mounting
</a
> and
112 <a href=
"http://bugs.debian.org/
581586">network setup
</a
> when
113 parallel booting is enabled. No idea why, but the wicd maintainer
114 seem to be on the case.
</li
>
116 <li
>The nvidia X driver seem to
117 <a href=
"http://bugs.debian.org/
583312">have a race condition
</a
>
118 triggered more easily when parallel booting is in effect. The
119 maintainer is on the case.
</li
>
121 <li
>The sysv-rc package fail to properly enable dependency based boot
122 sequencing (the shutdown is broken) when old file-rc users
123 <a href=
"http://bugs.debian.org/
575080">try to switch back
</a
> to
124 sysv-rc. One way to solve it would be for file-rc to create
125 /etc/init.d/.legacy-bootordering, and another is to try to make
126 sysv-rc more robust. Will investigate some more and probably upload a
127 workaround in sysv-rc to help those trying to move from file-rc to
128 sysv-rc get a working shutdown.
</li
>
130 </ul
></p
>
132 <p
>All in all not many surprising issues, and all of them seem
133 solvable before Squeeze is released. In addition to these there are
134 some packages with bugs in their dependencies and run level settings,
135 which I expect will be fixed in a reasonable time span.
</p
>
137 <p
>If you report any problems with dependencies in init.d scripts to
138 the BTS, please usertag the report to get it to show up at
139 <a href=
"http://bugs.debian.org/cgi-bin/pkgreport.cgi?users=initscripts-ng-devel@lists.alioth.debian.org
">the
140 list of usertagged bugs related to this
</a
>.
</p
>
142 <p
>Update: Correct bug number to file-rc issue.
</p
>
147 <title>More flexible firmware handling in debian-installer
</title>
148 <link>http://people.skolelinux.org/pere/blog/More_flexible_firmware_handling_in_debian_installer.html
</link>
149 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/More_flexible_firmware_handling_in_debian_installer.html
</guid>
150 <pubDate>Sat,
22 May
2010 21:
30:
00 +
0200</pubDate>
152 <p
>After a long break from debian-installer development, I finally
153 found time today to return to the project. Having to spend less time
154 working dependency based boot in debian, as it is almost complete now,
155 definitely helped freeing some time.
</p
>
157 <p
>A while back, I ran into a problem while working on Debian Edu. We
158 include some firmware packages on the Debian Edu CDs, those needed to
159 get disk and network controllers working. Without having these
160 firmware packages available during installation, it is impossible to
161 install Debian Edu on the given machine, and because our target group
162 are non-technical people, asking them to provide firmware packages on
163 an external medium is a support pain. Initially, I expected it to be
164 enough to include the firmware packages on the CD to get
165 debian-installer to find and use them. This proved to be wrong.
166 Next, I hoped it was enough to symlink the relevant firmware packages
167 to some useful location on the CD (tried /cdrom/ and
168 /cdrom/firmware/). This also proved to not work, and at this point I
169 found time to look at the debian-installer code to figure out what was
170 going to work.
</p
>
172 <p
>The firmware loading code is in the hw-detect package, and a closer
173 look revealed that it would only look for firmware packages outside
174 the installation media, so the CD was never checked for firmware
175 packages. It would only check USB sticks, floppies and other
176 "external
" media devices. Today I changed it to also look in the
177 /cdrom/firmware/ directory on the mounted CD or DVD, which should
178 solve the problem I ran into with Debian edu. I also changed it to
179 look in /firmware/, to make sure the installer also find firmware
180 provided in the initrd when booting the installer via PXE, to allow us
181 to provide the same feature in the PXE setup included in Debian
184 <p
>To make sure firmware deb packages with a license questions are not
185 activated without asking if the license is accepted, I extended
186 hw-detect to look for preinst scripts in the firmware packages, and
187 run these before activating the firmware during installation. The
188 license question is asked using debconf in the preinst, so this should
189 solve the issue for the firmware packages I have looked at so far.
</p
>
191 <p
>If you want to discuss the details of these features, please
192 contact us on debian-boot@lists.debian.org.
</p
>
197 <title>Magnetstripeinnhold i billetter fra Flytoget og Hurtigruten
</title>
198 <link>http://people.skolelinux.org/pere/blog/Magnetstripeinnhold_i_billetter_fra_Flytoget_og_Hurtigruten.html
</link>
199 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Magnetstripeinnhold_i_billetter_fra_Flytoget_og_Hurtigruten.html
</guid>
200 <pubDate>Fri,
21 May
2010 16:
00:
00 +
0200</pubDate>
202 <p
>For en stund tilbake kjøpte jeg en magnetkortleser for å kunne
203 titte på hva som er skrevet inn på magnetstripene til ulike kort. Har
204 ikke hatt tid til å analysere mange kort så langt, men tenkte jeg
205 skulle dele innholdet på to kort med mine lesere.
</p
>
207 <p
>For noen dager siden tok jeg flyet til Harstad og Hurtigruten til
208 Bergen. Flytoget fra Oslo S til flyplassen ga meg en billett med
209 magnetstripe. Påtrykket finner jeg følgende informasjon:
</p
>
212 Flytoget Airport Express Train
214 Fra - Til : Oslo Sentralstasjon
217 Herav mva.
8,
00% : NOK
12,
59
219 Til - Fra : Oslo Lufthavn
221 Gyldig Fra-Til :
08.05.10-
07.11.10
222 Billetttype : Enkeltbillett
224 102-
1015-
100508-
48382-
01-
08
227 <p
>På selve magnetstripen er innholdet
228 <tt
>;E?+
900120011=
23250996541068112619257138248441708433322932704083389389062603279671261502492655?
</tt
>.
229 Aner ikke hva innholdet representerer, og det er lite overlapp mellom
230 det jeg ser trykket på billetten og det jeg ser av tegn i
231 magnetstripen. Håper det betyr at de bruker kryptografiske metoder
232 for å gjøre det vanskelig å forfalske billetter.
</p
>
234 <p
>Den andre billetten er fra Hurtigruten, der jeg mistenker at
235 strekkoden på fronten er mer brukt enn magnetstripen (det var i hvert
236 fall den biten vi stakk inn i dørlåsen).
</p
>
238 <p
>Påtrykket forsiden er følgende:
</p
>
246 Bookingno: SAX69
0742193
248 Dep:
09.05.2010 Arr:
12.05.2010
253 <p
>På selve magnetstripen er innholdet
254 <tt
>;
1316010007421930=
00000000000000000000?+E?
</tt
>. Heller ikke her
255 ser jeg mye korrespondanse mellom påtrykk og magnetstripe.
</p
>
260 <title>Pieces of the roaming laptop puzzle in Debian
</title>
261 <link>http://people.skolelinux.org/pere/blog/Pieces_of_the_roaming_laptop_puzzle_in_Debian.html
</link>
262 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Pieces_of_the_roaming_laptop_puzzle_in_Debian.html
</guid>
263 <pubDate>Wed,
19 May
2010 19:
00:
00 +
0200</pubDate>
265 <p
>Today, the last piece of the puzzle for roaming laptops in Debian
266 Edu finally entered the Debian archive. Today, the new
267 <a href=
"http://packages.qa.debian.org/libp/libpam-mklocaluser.html
">libpam-mklocaluser
</a
>
268 package was accepted. Two days ago, two other pieces was accepted
270 <a href=
"http://packages.qa.debian.org/p/pam-python.html
">pam-python
</a
>
271 package needed by libpam-mklocaluser, and the
272 <a href=
"http://packages.qa.debian.org/s/sssd.html
">sssd
</a
> package
273 passed NEW on Monday. In addition, the
274 <a href=
"http://packages.qa.debian.org/libp/libpam-ccreds.html
">libpam-ccreds
</a
>
275 package we need is in experimental (version
10-
4) since Saturday, and
276 hopefully will be moved to unstable soon.
</p
>
278 <p
>This collection of packages allow for two different setups for
279 roaming laptops. The traditional setup would be using libpam-ccreds,
280 nscd and libpam-mklocaluser with LDAP or Kerberos authentication,
281 which should work out of the box if the configuration changes proposed
282 for nscd in
<a href=
"http://bugs.debian.org/
485282">BTS report
283 #
485282</a
> is implemented. The alternative setup is to use sssd with
284 libpam-mklocaluser to connect to LDAP or Kerberos and let sssd take
285 care of the caching of passwords and group information.
</p
>
287 <p
>I have so far been unable to get sssd to work with the LDAP server
288 at the University, but suspect the issue is some SSL/GnuTLS related
289 problem with the server certificate. I plan to update the Debian
290 package to version
1.2, which is scheduled for next week, and hope to
291 find time to make sure the next release will include both the
292 Debian/Ubuntu specific patches. Upstream is friendly and responsive,
293 and I am sure we will find a good solution.
</p
>
295 <p
>The idea is to set up the roaming laptops to authenticate using
296 LDAP or Kerberos and create a local user with home directory in /home/
297 when a usre in LDAP logs in via KDM or GDM for the first time, and
298 cache the password for offline checking, as well as caching group
299 memberhips and other relevant LDAP information. The
300 libpam-mklocaluser package was created to make sure the local home
301 directory is in /home/, instead of /site/server/directory/ which would
302 be the home directory if pam_mkhomedir was used. To avoid confusion
303 with support requests and configuration, we do not want local laptops
304 to have users in a path that is used for the same users home directory
305 on the home directory servers.
</p
>
307 <p
>One annoying problem with gdm is that it do not show the PAM
308 message passed to the user from libpam-mklocaluser when the local user
309 is created. Instead gdm simply reject the login with some generic
310 message. The message is shown in kdm, ssh and login, so I guess it is
311 a bug in gdm. Have not investigated if there is some other message
312 type that can be used instead to get gdm to also show the message.
</p
>
314 <p
>If you want to help out with implementing this for Debian Edu,
315 please contact us on debian-edu@lists.debian.org.
</p
>
320 <title>Parallellized boot is now the default in Debian/unstable
</title>
321 <link>http://people.skolelinux.org/pere/blog/Parallellized_boot_is_now_the_default_in_Debian_unstable.html
</link>
322 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Parallellized_boot_is_now_the_default_in_Debian_unstable.html
</guid>
323 <pubDate>Fri,
14 May
2010 22:
40:
00 +
0200</pubDate>
325 <p
>Since this evening, parallel booting is the default in
326 Debian/unstable for machines using dependency based boot sequencing.
327 Apparently the testing of concurrent booting has been wider than
328 expected, if I am to believe the
329 <a href=
"http://lists.debian.org/debian-devel/
2010/
05/msg00122.html
">input
330 on debian-devel@
</a
>, and I concluded a few days ago to move forward
331 with the feature this weekend, to give us some time to detect any
332 remaining problems before Squeeze is frozen. If serious problems are
333 detected, it is simple to change the default back to sequential boot.
334 The upload of the new sysvinit package also activate a new upstream
337 More information about
338 <a href=
"http://wiki.debian.org/LSBInitScripts/DependencyBasedBoot
">dependency
339 based boot sequencing
</a
> is available from the Debian wiki. It is
340 currently possible to disable parallel booting when one run into
341 problems caused by it, by adding this line to /etc/default/rcS:
</p
>
343 <blockquote
><pre
>
345 </pre
></blockquote
>
347 <p
>If you report any problems with dependencies in init.d scripts to
348 the BTS, please usertag the report to get it to show up at
349 <a href=
"http://bugs.debian.org/cgi-bin/pkgreport.cgi?users=initscripts-ng-devel@lists.alioth.debian.org
">the
350 list of usertagged bugs related to this
</a
>.
</p
>
355 <title>Sitesummary tip: Listing MAC address of all clients
</title>
356 <link>http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_MAC_address_of_all_clients.html
</link>
357 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/Sitesummary_tip__Listing_MAC_address_of_all_clients.html
</guid>
358 <pubDate>Fri,
14 May
2010 21:
10:
00 +
0200</pubDate>
360 <p
>In the recent Debian Edu versions, the
361 <a href=
"http://wiki.debian.org/DebianEdu/HowTo/SiteSummary
">sitesummary
362 system
</a
> is used to keep track of the machines in the school
363 network. Each machine will automatically report its status to the
364 central server after boot and once per night. The network setup is
365 also reported, and using this information it is possible to get the
366 MAC address of all network interfaces in the machines. This is useful
367 to update the DHCP configuration.
</p
>
369 <p
>To give some idea how to use sitesummary, here is a one-liner to
370 ist all MAC addresses of all machines reporting to sitesummary. Run
371 this on the collector host:
</p
>
373 <blockquote
><pre
>
374 perl -MSiteSummary -e
'for_all_hosts(sub { print join(
" ", get_macaddresses(shift)),
"\n
"; });
'
375 </pre
></blockquote
>
377 <p
>This will list all MAC addresses assosiated with all machine, one
378 line per machine and with space between the MAC addresses.
</p
>
380 <p
>To allow system administrators easier job at adding static DHCP
381 addresses for hosts, it would be possible to extend this to fetch
382 machine information from sitesummary and update the DHCP and DNS
383 tables in LDAP using this information. Such tool is unfortunately not
384 written yet.
</p
>
389 <title>systemd, an interesting alternative to upstart
</title>
390 <link>http://people.skolelinux.org/pere/blog/systemd__an_interesting_alternative_to_upstart.html
</link>
391 <guid isPermaLink=
"true">http://people.skolelinux.org/pere/blog/systemd__an_interesting_alternative_to_upstart.html
</guid>
392 <pubDate>Thu,
13 May
2010 22:
20:
00 +
0200</pubDate>
394 <p
>The last few days a new boot system called
395 <a href=
"http://www.freedesktop.org/wiki/Software/systemd
">systemd
</a
>
397 <a href=
"http://
0pointer.de/blog/projects/systemd.html
">introduced
</a
>
399 to the free software world. I have not yet had time to play around
400 with it, but it seem to be a very interesting alternative to
401 <a href=
"http://upstart.ubuntu.com/
">upstart
</a
>, and might prove to be
402 a good alternative for Debian when we are able to switch to an event
403 based boot system. Tollef is
404 <a href=
"http://bugs.debian.org/
580814">in the process
</a
> of getting
405 systemd into Debian, and I look forward to seeing how well it work. I
406 like the fact that systemd handles init.d scripts with dependency
407 information natively, allowing them to run in parallel where upstart
408 at the moment do not.
</p
>
410 <p
>Unfortunately do systemd have the same problem as upstart regarding
411 platform support. It only work on recent Linux kernels, and also need
412 some new kernel features enabled to function properly. This means
413 kFreeBSD and Hurd ports of Debian will need a port or a different boot
414 system. Not sure how that will be handled if systemd proves to be the
415 way forward.
</p
>
417 <p
>In the mean time, based on the
418 <a href=
"http://lists.debian.org/debian-devel/
2010/
05/msg00122.html
">input
419 on debian-devel@
</a
> regarding parallel booting in Debian, I have
420 decided to enable full parallel booting as the default in Debian as
421 soon as possible (probably this weekend or early next week), to see if
422 there are any remaining serious bugs in the init.d dependencies. A
423 new version of the sysvinit package implementing this change is
424 already in experimental. If all go well, Squeeze will be released
425 with parallel booting enabled by default.
</p
>