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  14        <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  15
  16   </h1>
  17
  18  </div>
  19
  20
  21
  22  <div class="entry">
  23   <div class="title"><a href="http://people.skolelinux.org/pere/blog/Circular_package_dependencies_harms_apt_recovery.html">Circular package dependencies harms apt recovery</a></div>
  24   <div class="date">2010-07-27 23:50</div>
  25   <div class="body">
  26 <p>I discovered this while doing
  27 <a href="http://people.skolelinux.org/pere/blog/Automatic_upgrade_testing_from_Lenny_to_Squeeze.html">automated
  28 testing of upgrades from Debian Lenny to Squeeze</a>.  A few packages
  29 in Debian still got circular dependencies, and it is often claimed
  30 that apt and aptitude should be able to handle this just fine, but
  31 some times these dependency loops causes apt to fail.</p>
  32
  33 <p>An example is from todays
  34 <a href="http://people.skolelinux.org/~pere/debian-upgrade-testing//test-20100727-lenny-squeeze-kde-aptitude.txt">upgrade
  35 of KDE using aptitude</a>.  In it, a bug in kdebase-workspace-data
  36 causes perl-modules to fail to upgrade.  The cause is simple.  If a
  37 package fail to unpack, then only part of packages with the circular
  38 dependency might end up being unpacked when unpacking aborts, and the
  39 ones already unpacked will fail to configure in the recovery phase
  40 because its dependencies are unavailable.</p>
  41
  42 <p>In this log, the problem manifest itself with this error:</p>
  43
  44 <blockquote><pre>
  45 dpkg: dependency problems prevent configuration of perl-modules:
  46  perl-modules depends on perl (>= 5.10.1-1); however:
  47   Version of perl on system is 5.10.0-19lenny2.
  48 dpkg: error processing perl-modules (--configure):
  49  dependency problems - leaving unconfigured
  50 </pre></blockquote>
  51
  52 <p>The perl/perl-modules circular dependency is already
  53 <a href="http://bugs.debian.org/527917">reported as a bug</a>, and will
  54 hopefully be solved as soon as possible, but it is not the only one,
  55 and each one of these loops in the dependency tree can cause similar
  56 failures.  Of course, they only occur when there are bugs in other
  57 packages causing the unpacking to fail, but it is rather nasty when
  58 the failure of one package causes the problem to become worse because
  59 of dependency loops.</p>
  60
  61 <p>Thanks to
  62 <a href="http://lists.debian.org/debian-devel/2010/06/msg00116.html">the
  63 tireless effort by Bill Allombert</a>, the number of circular
  64 dependencies
  65 <a href="http://debian.semistable.com/debgraph.out.html">left in Debian
  66 is dropping</a>, and perhaps it will reach zero one day. :)</p>
  67
  68 <p>Todays testing also exposed a bug in
  69 <a href="http://bugs.debian.org/590605">update-notifier</a> and
  70 <a href="http://bugs.debian.org/590604">different behaviour</a> between
  71 apt-get and aptitude, the latter possibly caused by some circular
  72 dependency.  Reported both to BTS to try to get someone to look at
  73 it.</p>
  74 </div>
  75   <div class="tags">
  76
  77
  78
  79    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
  80
  81   </div>
  82  </div>
  83  <div class="padding"></div>
  84
  85  <div class="entry">
  86   <div class="title"><a href="http://people.skolelinux.org/pere/blog/First_Debian_Edu_test_release__alpha0__based_on_Squeeze_is_released.html">First Debian Edu test release (alpha0) based on Squeeze is released</a></div>
  87   <div class="date">2010-07-27 17:45</div>
  88   <div class="body">
  89 <p>I just posted this announcement culminating several months of work
  90 with the next Debian Edu release.  Not nearly done, but one major step
  91 completed.</p>
  92
  93 <blockquote>
  94 <p>This is the first test release based on Squeeze. The focus of this
  95 release is to test the user application selection. To have a look,
  96 install the standalone profile and let the developers know if the set
  97 of installed packages i.e. applications should be modified. If some
  98 user application is missing, or if there are some applications that no
  99 longer make sense to be included in Debian Edu, please let us know.
 100 Also, if a useful application is missing the translation for your
 101 language of choice, please let us know too.</p>
 102
 103 <p>In addition, feedback and help to polish the desktop (menus,
 104 artwork, starters, etc.) is appreciated. We would like to ship a nice
 105 and handy KDE4 desktop targeted for schools out of the box.</p>
 106
 107 <p>The other profiles should be installable, but there is a lot more
 108 work left to be done before they are ready, so do not expect to
 109 much.</p>
 110
 111 <p>Changes compared to the lenny based version</p>
 112
 113 <ul>
 114 <li>Everything from Debian Squeeze
 115 <ul>
 116   <li>Desktop environment KDE 4.4 => the new KDE desktop in
 117          combination with some new artwork
 118   <li>Web browser Iceweasel 3.5
 119   <li>OpenOffice.org 3.2
 120   <li>Educational toolbox GCompris 9.3
 121   <li>Music creator Rosegarden 10.04.2
 122   <li>Image editor Gimp 2.6.10
 123   <li>Virtual universe Celestia 1.6.0
 124   <li>Virtual stargazer Stellarium 0.10.4
 125   <li>3D modeler Blender 2.49.2 (new application)
 126   <li>Video editor Kdenlive 0.7.7 (new application)
 127 </ul></li>
 128 <li>Now using Kerberos for password checking (migration not finished).
 129     Enabled for:
 130 <ul>
 131   <li>PAM
 132   <li>LDAP
 133   <li>IMAP
 134   <li>SMTP (sender verification)
 135 </ul>
 136 </li>
 137 <li>New experimental roaming workstation profile for laptops.</li>
 138 <li>Show welcome page to users when they first log in. The URL is
 139     fetched from LDAP.</li>
 140 <li>New LXDE desktop option, in addition to KDE (default) and Gnome.</li>
 141 <li>General cleanup (not finished)</li>
 142 </ul>
 143 <p>The following features are not working as they should</p>
 144
 145 <ul>
 146 <li>No web based administration tool for creating users and groups. The
 147     scripts ldap-createuser-krb and ldap-add-user-to-group can be used
 148     for testing.</li>
 149 <li>DVD installs are missing debian-installer images for the PXE boot,
 150     and do not set up the PXE menu on eth0 because of this. LTSP
 151     clients should still boot from eth1 on thin client servers.</li>
 152 <li>The restructured KDE menu is not implemented.</li>
 153 <li>The LDAP server setup need to be reviewed for security.</li>
 154 <li>The LDAP directory structure need to be reworked.</li>
 155 <li>Different sets of packages are installed when using the DVD and the
 156     netinst CD. More packages are installed using the netinst CD.</li>
 157 <li>The jackd package fail to install. This is believed to be caused by
 158     some ongoing transition, and hopefully should be solved soon. The
 159     jackd1 package can be installed manually for those that need it.</li>
 160 <li>Some packages lack translations. See
 161     http://wiki.debian.org/DebianEdu/Status/Squeeze for updated status,
 162     and help out with translations.</li>
 163 </ul>
 164
 165 <p>To download this multiarch netinstall release you can use</p>
 166
 167 <ul>
 168 <li><a href="ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso">ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso</a></li>
 169 <li><a href="http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso">http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso</a></li>
 170 <li>rsync -avzP ftp.skolelinux.org::skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-CD.iso</li>
 171 </ul>
 172 <p>To download this multiarch dvd release you can use</p>
 173
 174 <ul>
 175 <li><a href="ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso">ftp://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso</a></li>
 176 <li><a href="http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso">http://ftp.skolelinux.org/skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso</a></li>
 177 <li>rsync -avzP ftp.skolelinux.org::skolelinux-cd/squeeze-alpha/debian-edu-6.0.0+edua0-DVD.iso</li>
 178 </ul>
 179
 180 <p>There is no source DVD available yet. It will be prepared when we
 181 get closer to the final release.</p>
 182
 183 <p>The MD5SUM of these images are</p>
 184
 185 <ul>
 186 <li>3dbf45d59f42a53518b6e3c9ec3b5eb6 debian-edu-6.0.0+edua0-CD.iso</li>
 187 <li>22f2cbfce281d1c6e478be452638675d debian-edu-6.0.0+edua0-DVD.iso</li>
 188 </ul>
 189
 190 <p>The SHA1SUM of these images are</p>
 191 <ul>
 192 <li>c53d1b69b40cf37cd27aefaf33f6f6a3821bedf0 debian-edu-6.0.0+edua0-CD.iso</li>
 193 <li>2ec29d7db676d59d32197b05c277ffe16348376c debian-edu-6.0.0+edua0-DVD.iso</li>
 194 </ul>
 195 <p>How to report bugs:
 196 http://wiki.debian.org/DebianEdu/HowTo/ReportBugsInBugzilla</p>
 197
 198 <p>Please direct replies to debian-edu@lists.debian.org</p>
 199 </blockquote>
 200 </div>
 201   <div class="tags">
 202
 203
 204
 205    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 206
 207   </div>
 208  </div>
 209  <div class="padding"></div>
 210
 211  <div class="entry">
 212   <div class="title"><a href="http://people.skolelinux.org/pere/blog/One_step_closer_to_single_signon_in_Debian_Edu.html">One step closer to single signon in Debian Edu</a></div>
 213   <div class="date">2010-07-25 10:00</div>
 214   <div class="body">
 215 <p>The last few months me and the other Debian Edu developers have
 216 been working hard to get the Debian/Squeeze based version of Debian
 217 Edu/Skolelinux into shape.  This future version will use Kerberos for
 218 authentication, and services are slowly migrated to single signon,
 219 getting rid of password questions one at the time.</p>
 220
 221 <p>It will also feature a roaming workstation profile with local home
 222 directory, for laptops that are only some times on the Skolelinux
 223 network, and for this profile a shortcut is created in Gnome and KDE
 224 to gain access to the users home directory on the file server.  This
 225 shortcut uses SMB at the moment, and yesterday I had time to test if
 226 SMB mounting had started working in KDE after we added the cifs-utils
 227 package.  I was pleasantly surprised how well it worked.</p>
 228
 229 <p>Thanks to the recent changes to our samba configuration to get it
 230 to use Kerberos for authentication, there were no question about user
 231 password when mounting the SMB volume.  A simple click on the shortcut
 232 in the KDE menu, and a window with the home directory popped
 233 up. :)</p>
 234
 235 <p>One step closer to a single signon solution out of the box in
 236 Debian Edu.  We already had PAM, LDAP, IMAP and SMTP in place, and now
 237 also Samba.  Next step is Cups and hopefully also NFS.</p>
 238
 239 <p>We had planned a alpha0 release of Debian Edu for today, but thanks
 240 to the autobuilder administrators for some architectures being slow to
 241 sign packages, we are still missing the fixed LTSP package we need for
 242 the release.  It was uploaded three days ago with urgency=high, and if
 243 it had entered testing yesterday we would have been able to test it in
 244 time for a alpha0 release today.  As the binaries for ia64 and powerpc
 245 still not uploaded to the Debian archive, we need to delay the alpha
 246 release another day.</p>
 247
 248 <p>If you want to help out with implementing Kerberos for Debian Edu,
 249 please contact us on debian-edu@lists.debian.org.</p>
 250 </div>
 251   <div class="tags">
 252
 253
 254
 255    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>.
 256
 257   </div>
 258  </div>
 259  <div class="padding"></div>
 260
 261  <div class="entry">
 262   <div class="title"><a href="http://people.skolelinux.org/pere/blog/Digitale_restriksjonsmekanismer_fikk_meg_til____slutte____kj__pe_musikk.html">Digitale restriksjonsmekanismer fikk meg til å slutte å kjøpe musikk</a></div>
 263   <div class="date">2010-07-22 23:50</div>
 264   <div class="body">
 265 <p>For mange år siden slutte jeg å kjøpe musikk-CDer. Årsaken var at
 266 musikkbransjen var godt i gang med å selge platene sine med DRM som
 267 gjorde at jeg ikke fikk spilt av musikken jeg kjøpte på utstyret jeg
 268 hadde tilgjengelig, dvs. min datamaskin. Det var umulig å se på en
 269 plate om den var ødelagt eller ikke, og jeg hadde jo allerede en
 270 anseelig samling med plater, så jeg bestemme meg for å slutte å gi
 271 penger til en bransje som åpenbart ikke respekterte meg.</p>
 272
 273 <p>Jeg har mange titalls dager med musikk på CD i dag. Det meste er
 274 lagt i et stort arkiv som kan spilles av fra husets datamaskiner (har
 275 ikke rukket rippe alt). Jeg ser dermed ikke behovet for å skaffe mer
 276 musikk. De fleste av mine favoritter er i hus, og jeg er dermed godt
 277 fornøyd.</p>
 278
 279 <p>Hvis musikkbransjen ønsker mine penger, så må de demonstrere at de
 280 setter pris på meg som kunde, og ikke skremme meg bort med DRM og
 281 antydninger om at kundene er kriminelle.</p>
 282
 283 <p>Filmbransjen er like ille, men mens musikk gjerne varer lenge, er
 284 filmer mer ferskvare. Har dermed ikke helt sluttet å kjøpe filmer, men
 285 holder meg til DVD-filmer som kan spilles av på mine Linuxbokser.
 286 Kommer neppe til å ta i bruk Blueray, og ei heller de nye DRM-greiene
 287 «Ultraviolet» som be annonsert her om dagen.</p>
 288 </div>
 289   <div class="tags">
 290
 291
 292
 293    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling</a>, <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>, <a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>.
 294
 295   </div>
 296  </div>
 297  <div class="padding"></div>
 298
 299  <div class="entry">
 300   <div class="title"><a href="http://people.skolelinux.org/pere/blog/OpenStreetmap_one_step_closer_to_having_routing_on_its_front_page.html">OpenStreetmap one step closer to having routing on its front page</a></div>
 301   <div class="date">2010-07-18 16:45</div>
 302   <div class="body">
 303 <p>Thanks to
 304 <a href="http://feedproxy.google.com/~r/Opengeodata/~3/wUTCzDZk3lc/project-of-the-week-which-way-home">todays
 305 opengeodata blog entry</a>, I just discovered that the
 306 OpenStreetmap.org site have gotten
 307 <a href="http://nroets.dev.openstreetmap.org/demo/index.html?layers=B000FTFTT">support
 308 for calculating routes</a>.  The support is still experimental and
 309 only available from the development server, until more experience is
 310 gathered on the user interface and any scalability issues.</p>
 311
 312 <p>Earlier, the routing I knew about using the OpenStreetmap.org data
 313 was provided by <a href="http://maps.cloudmade.com/">Cloudmade</a>,
 314 but having it on the main page is required to make everyone aware of
 315 the issue.  I've had people reject Openstreetmap.org as a viable
 316 alternative for them because the front page lacked routing support,
 317 and I hope their needs will be catered for when routing show up on the
 318 www.openstreetmap.org front page.</p>
 319 </div>
 320   <div class="tags">
 321
 322
 323
 324    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/kart">kart</a>, <a href="http://people.skolelinux.org/pere/blog/tags/web">web</a>.
 325
 326   </div>
 327  </div>
 328  <div class="padding"></div>
 329
 330  <div class="entry">
 331   <div class="title"><a href="http://people.skolelinux.org/pere/blog/What_are_they_searching_for___PowerDNS_and_ISC_DHCP_in_LDAP.html">What are they searching for - PowerDNS and ISC DHCP in LDAP</a></div>
 332   <div class="date">2010-07-17 21:00</div>
 333   <div class="body">
 334 <p>This is a
 335 <a href="http://people.skolelinux.org/pere/blog/Time_for_new__LDAP_schemas_replacing_RFC_2307_.html">followup</a>
 336 on my
 337 <a href="http://people.skolelinux.org/pere/blog/Idea_for_a_change_to_LDAP_schemas_allowing_DNS_and_DHCP_info_to_be_combined_into_one_object.html">previous
 338 work</a> on
 339 <a href="http://people.skolelinux.org/pere/blog/Combining_PowerDNS_and_ISC_DHCP_LDAP_objects.html">merging
 340 all</a> the computer related LDAP objects in Debian Edu.</p>
 341
 342 <p>As a step to try to see if it possible to merge the DNS and DHCP
 343 LDAP objects, I have had a look at how the packages pdns-backend-ldap
 344 and dhcp3-server-ldap in Debian use the LDAP server.  The two
 345 implementations are quite different in how they use LDAP.</p>
 346
 347 To get this information, I started slapd with debugging enabled and
 348 dumped the debug output to a file to get the LDAP searches performed
 349 on a Debian Edu main-server.  Here is a summary.
 350
 351 <p><strong>powerdns</strong></p>
 352
 353 <a href="http://www.linuxnetworks.de/doc/index.php/PowerDNS_LDAP_Backend">Clues
 354 on how to</a> set up PowerDNS to use a LDAP backend is available on
 355 the web.
 356
 357 <p>PowerDNS have two modes of operation using LDAP as its backend.
 358 One "strict" mode where the forward and reverse DNS lookups are done
 359 using the same LDAP objects, and a "tree" mode where the forward and
 360 reverse entries are in two different subtrees in LDAP with a structure
 361 based on the DNS names, as in tjener.intern and
 362 2.2.0.10.in-addr.arpa.</p>
 363
 364 <p>In tree mode, the server is set up to use a LDAP subtree as its
 365 base, and uses a "base" scoped search for the DNS name by adding
 366 "dc=tjener,dc=intern," to the base with a filter for
 367 "(associateddomain=tjener.intern)" for the forward entry and
 368 "dc=2,dc=2,dc=0,dc=10,dc=in-addr,dc=arpa," with a filter for
 369 "(associateddomain=2.2.0.10.in-addr.arpa)" for the reverse entry.  For
 370 forward entries, it is looking for attributes named dnsttl, arecord,
 371 nsrecord, cnamerecord, soarecord, ptrrecord, hinforecord, mxrecord,
 372 txtrecord, rprecord, afsdbrecord, keyrecord, aaaarecord, locrecord,
 373 srvrecord, naptrrecord, kxrecord, certrecord, dsrecord, sshfprecord,
 374 ipseckeyrecord, rrsigrecord, nsecrecord, dnskeyrecord, dhcidrecord,
 375 spfrecord and modifytimestamp.  For reverse entries it is looking for
 376 the attributes dnsttl, arecord, nsrecord, cnamerecord, soarecord,
 377 ptrrecord, hinforecord, mxrecord, txtrecord, rprecord, aaaarecord,
 378 locrecord, srvrecord, naptrrecord and modifytimestamp.  The equivalent
 379 ldapsearch commands could look like this:</p>
 380
 381 <blockquote><pre>
 382 ldapsearch -h ldap \
 383   -b dc=tjener,dc=intern,ou=hosts,dc=skole,dc=skolelinux,dc=no \
 384   -s base -x '(associateddomain=tjener.intern)' dNSTTL aRecord nSRecord \
 385   cNAMERecord sOARecord pTRRecord hInfoRecord mXRecord tXTRecord \
 386   rPRecord aFSDBRecord KeyRecord aAAARecord lOCRecord sRVRecord \
 387   nAPTRRecord kXRecord certRecord dSRecord sSHFPRecord iPSecKeyRecord \
 388   rRSIGRecord nSECRecord dNSKeyRecord dHCIDRecord sPFRecord modifyTimestamp
 389
 390 ldapsearch -h ldap \
 391   -b dc=2,dc=2,dc=0,dc=10,dc=in-addr,dc=arpa,ou=hosts,dc=skole,dc=skolelinux,dc=no \
 392   -s base -x '(associateddomain=2.2.0.10.in-addr.arpa)'
 393   dnsttl, arecord, nsrecord, cnamerecord soarecord ptrrecord \
 394   hinforecord mxrecord txtrecord rprecord aaaarecord locrecord \
 395   srvrecord naptrrecord modifytimestamp
 396 </pre></blockquote>
 397
 398 <p>In Debian Edu/Lenny, the PowerDNS tree mode is used with
 399 ou=hosts,dc=skole,dc=skolelinux,dc=no as the base, and these are two
 400 example LDAP objects used there.  In addition to these objects, the
 401 parent objects all th way up to ou=hosts,dc=skole,dc=skolelinux,dc=no
 402 also exist.</p>
 403
 404 <blockquote><pre>
 405 dn: dc=tjener,dc=intern,ou=hosts,dc=skole,dc=skolelinux,dc=no
 406 objectclass: top
 407 objectclass: dnsdomain
 408 objectclass: domainrelatedobject
 409 dc: tjener
 410 arecord: 10.0.2.2
 411 associateddomain: tjener.intern
 412
 413 dn: dc=2,dc=2,dc=0,dc=10,dc=in-addr,dc=arpa,ou=hosts,dc=skole,dc=skolelinux,dc=no
 414 objectclass: top
 415 objectclass: dnsdomain2
 416 objectclass: domainrelatedobject
 417 dc: 2
 418 ptrrecord: tjener.intern
 419 associateddomain: 2.2.0.10.in-addr.arpa
 420 </pre></blockquote>
 421
 422 <p>In strict mode, the server behaves differently.  When looking for
 423 forward DNS entries, it is doing a "subtree" scoped search with the
 424 same base as in the tree mode for a object with filter
 425 "(associateddomain=tjener.intern)" and requests the attributes dnsttl,
 426 arecord, nsrecord, cnamerecord, soarecord, ptrrecord, hinforecord,
 427 mxrecord, txtrecord, rprecord, aaaarecord, locrecord, srvrecord,
 428 naptrrecord and modifytimestamp.  For reverse entires it also do a
 429 subtree scoped search but this time the filter is "(arecord=10.0.2.2)"
 430 and the requested attributes are associateddomain, dnsttl and
 431 modifytimestamp.  In short, in strict mode the objects with ptrrecord
 432 go away, and the arecord attribute in the forward object is used
 433 instead.</p>
 434
 435 <p>The forward and reverse searches can be simulated using ldapsearch
 436 like this:</p>
 437
 438 <blockquote><pre>
 439 ldapsearch -h ldap -b ou=hosts,dc=skole,dc=skolelinux,dc=no -s sub -x \
 440   '(associateddomain=tjener.intern)' dNSTTL aRecord nSRecord \
 441   cNAMERecord sOARecord pTRRecord hInfoRecord mXRecord tXTRecord \
 442   rPRecord aFSDBRecord KeyRecord aAAARecord lOCRecord sRVRecord \
 443   nAPTRRecord kXRecord certRecord dSRecord sSHFPRecord iPSecKeyRecord \
 444   rRSIGRecord nSECRecord dNSKeyRecord dHCIDRecord sPFRecord modifyTimestamp
 445
 446 ldapsearch -h ldap -b ou=hosts,dc=skole,dc=skolelinux,dc=no -s sub -x \
 447   '(arecord=10.0.2.2)' associateddomain dnsttl modifytimestamp
 448 </pre></blockquote>
 449
 450 <p>In addition to the forward and reverse searches , there is also a
 451 search for SOA records, which behave similar to the forward and
 452 reverse lookups.</p>
 453
 454 <p>A thing to note with the PowerDNS behaviour is that it do not
 455 specify any objectclass names, and instead look for the attributes it
 456 need to generate a DNS reply.  This make it able to work with any
 457 objectclass that provide the needed attributes.</p>
 458
 459 <p>The attributes are normally provided in the cosine (RFC 1274) and
 460 dnsdomain2 schemas.  The latter is used for reverse entries like
 461 ptrrecord and recent DNS additions like aaaarecord and srvrecord.</p>
 462
 463 <p>In Debian Edu, we have created DNS objects using the object classes
 464 dcobject (for dc), dnsdomain or dnsdomain2 (structural, for the DNS
 465 attributes) and domainrelatedobject (for associatedDomain).  The use
 466 of structural object classes make it impossible to combine these
 467 classes with the object classes used by DHCP.</p>
 468
 469 <p>There are other schemas that could be used too, for example the
 470 dnszone structural object class used by Gosa and bind-sdb for the DNS
 471 attributes combined with the domainrelatedobject object class, but in
 472 this case some unused attributes would have to be included as well
 473 (zonename and relativedomainname).</p>
 474
 475 <p>My proposal for Debian Edu would be to switch PowerDNS to strict
 476 mode and not use any of the existing objectclasses (dnsdomain,
 477 dnsdomain2 and dnszone) when one want to combine the DNS information
 478 with DHCP information, and instead create a auxiliary object class
 479 defined something like this (using the attributes defined for
 480 dnsdomain and dnsdomain2 or dnszone):</p>
 481
 482 <blockquote><pre>
 483 objectclass ( some-oid NAME 'dnsDomainAux'
 484     SUP top
 485     AUXILIARY
 486     MAY ( ARecord $ MDRecord $ MXRecord $ NSRecord $ SOARecord $ CNAMERecord $
 487           DNSTTL $ DNSClass $ PTRRecord $ HINFORecord $ MINFORecord $
 488           TXTRecord $ SIGRecord $ KEYRecord $ AAAARecord $ LOCRecord $
 489           NXTRecord $ SRVRecord $ NAPTRRecord $ KXRecord $ CERTRecord $
 490           A6Record $ DNAMERecord
 491     ))
 492 </pre></blockquote>
 493
 494 <p>This will allow any object to become a DNS entry when combined with
 495 the domainrelatedobject object class, and allow any entity to include
 496 all the attributes PowerDNS wants.  I've sent an email to the PowerDNS
 497 developers asking for their view on this schema and if they are
 498 interested in providing such schema with PowerDNS, and I hope my
 499 message will be accepted into their mailing list soon.</p>
 500
 501 <p><strong>ISC dhcp</strong></p>
 502
 503 <p>The DHCP server searches for specific objectclass and requests all
 504 the object attributes, and then uses the attributes it want.  This
 505 make it harder to figure out exactly what attributes are used, but
 506 thanks to the working example in Debian Edu I can at least get an idea
 507 what is needed without having to read the source code.</p>
 508
 509 <p>In the DHCP server configuration, the LDAP base to use and the
 510 search filter to use to locate the correct dhcpServer entity is
 511 stored.  These are the relevant entries from
 512 /etc/dhcp3/dhcpd.conf:</p>
 513
 514 <blockquote><pre>
 515 ldap-base-dn "dc=skole,dc=skolelinux,dc=no";
 516 ldap-dhcp-server-cn "dhcp";
 517 </pre></blockquote>
 518
 519 <p>The DHCP server uses this information to nest all the DHCP
 520 configuration it need.  The cn "dhcp" is located using the given LDAP
 521 base and the filter "(&(objectClass=dhcpServer)(cn=dhcp))".  The
 522 search result is this entry:</p>
 523
 524 <blockquote><pre>
 525 dn: cn=dhcp,dc=skole,dc=skolelinux,dc=no
 526 cn: dhcp
 527 objectClass: top
 528 objectClass: dhcpServer
 529 dhcpServiceDN: cn=DHCP Config,dc=skole,dc=skolelinux,dc=no
 530 </pre></blockquote>
 531
 532 <p>The content of the dhcpServiceDN attribute is next used to locate the
 533 subtree with DHCP configuration.  The DHCP configuration subtree base
 534 is located using a base scope search with base "cn=DHCP
 535 Config,dc=skole,dc=skolelinux,dc=no" and filter
 536 "(&(objectClass=dhcpService)(|(dhcpPrimaryDN=cn=dhcp,dc=skole,dc=skolelinux,dc=no)(dhcpSecondaryDN=cn=dhcp,dc=skole,dc=skolelinux,dc=no)))".
 537 The search result is this entry:</p>
 538
 539 <blockquote><pre>
 540 dn: cn=DHCP Config,dc=skole,dc=skolelinux,dc=no
 541 cn: DHCP Config
 542 objectClass: top
 543 objectClass: dhcpService
 544 objectClass: dhcpOptions
 545 dhcpPrimaryDN: cn=dhcp, dc=skole,dc=skolelinux,dc=no
 546 dhcpStatements: ddns-update-style none
 547 dhcpStatements: authoritative
 548 dhcpOption: smtp-server code 69 = array of ip-address
 549 dhcpOption: www-server code 72 = array of ip-address
 550 dhcpOption: wpad-url code 252 = text
 551 </pre></blockquote>
 552
 553 <p>Next, the entire subtree is processed, one level at the time.  When
 554 all the DHCP configuration is loaded, it is ready to receive requests.
 555 The subtree in Debian Edu contain objects with object classes
 556 top/dhcpService/dhcpOptions, top/dhcpSharedNetwork/dhcpOptions,
 557 top/dhcpSubnet, top/dhcpGroup and top/dhcpHost.  These provide options
 558 and information about netmasks, dynamic range etc.  Leaving out the
 559 details here because it is not relevant for the focus of my
 560 investigation, which is to see if it is possible to merge dns and dhcp
 561 related computer objects.</p>
 562
 563 <p>When a DHCP request come in, LDAP is searched for the MAC address
 564 of the client (00:00:00:00:00:00 in this example), using a subtree
 565 scoped search with "cn=DHCP Config,dc=skole,dc=skolelinux,dc=no" as
 566 the base and "(&(objectClass=dhcpHost)(dhcpHWAddress=ethernet
 567 00:00:00:00:00:00))" as the filter.  This is what a host object look
 568 like:</p>
 569
 570 <blockquote><pre>
 571 dn: cn=hostname,cn=group1,cn=THINCLIENTS,cn=DHCP Config,dc=skole,dc=skolelinux,dc=no
 572 cn: hostname
 573 objectClass: top
 574 objectClass: dhcpHost
 575 dhcpHWAddress: ethernet 00:00:00:00:00:00
 576 dhcpStatements: fixed-address hostname
 577 </pre></blockquote>
 578
 579 <p>There is less flexiblity in the way LDAP searches are done here.
 580 The object classes need to have fixed names, and the configuration
 581 need to be stored in a fairly specific LDAP structure.  On the
 582 positive side, the invidiual dhcpHost entires can be anywhere without
 583 the DN pointed to by the dhcpServer entries.  The latter should make
 584 it possible to group all host entries in a subtree next to the
 585 configuration entries, and this subtree can also be shared with the
 586 DNS server if the schema proposed above is combined with the dhcpHost
 587 structural object class.
 588
 589 <p><strong>Conclusion</strong></p>
 590
 591 <p>The PowerDNS implementation seem to be very flexible when it come
 592 to which LDAP schemas to use.  While its "tree" mode is rigid when it
 593 come to the the LDAP structure, the "strict" mode is very flexible,
 594 allowing DNS objects to be stored anywhere under the base cn specified
 595 in the configuration.</p>
 596
 597 <p>The DHCP implementation on the other hand is very inflexible, both
 598 regarding which LDAP schemas to use and which LDAP structure to use.
 599 I guess one could implement ones own schema, as long as the
 600 objectclasses and attributes have the names used, but this do not
 601 really help when the DHCP subtree need to have a fairly fixed
 602 structure.</p>
 603
 604 <p>Based on the observed behaviour, I suspect a LDAP structure like
 605 this might work for Debian Edu:</p>
 606
 607 <blockquote><pre>
 608 ou=services
 609   cn=machine-info (dhcpService) - dhcpServiceDN points here
 610     cn=dhcp (dhcpServer)
 611     cn=dhcp-internal (dhcpSharedNetwork/dhcpOptions)
 612       cn=10.0.2.0 (dhcpSubnet)
 613         cn=group1 (dhcpGroup/dhcpOptions)
 614     cn=dhcp-thinclients (dhcpSharedNetwork/dhcpOptions)
 615       cn=192.168.0.0 (dhcpSubnet)
 616         cn=group1 (dhcpGroup/dhcpOptions)
 617     ou=machines - PowerDNS base points here
 618       cn=hostname (dhcpHost/domainrelatedobject/dnsDomainAux)
 619 </pre></blockquote>
 620
 621 <P>This is not tested yet.  If the DHCP server require the dhcpHost
 622 entries to be in the dhcpGroup subtrees, the entries can be stored
 623 there instead of a common machines subtree, and the PowerDNS base
 624 would have to be moved one level up to the machine-info subtree.</p>
 625
 626 <p>The combined object under the machines subtree would look something
 627 like this:</p>
 628
 629 <blockquote><pre>
 630 dn: dc=hostname,ou=machines,cn=machine-info,dc=skole,dc=skolelinux,dc=no
 631 dc: hostname
 632 objectClass: top
 633 objectClass: dhcpHost
 634 objectclass: domainrelatedobject
 635 objectclass: dnsDomainAux
 636 associateddomain: hostname.intern
 637 arecord: 10.11.12.13
 638 dhcpHWAddress: ethernet 00:00:00:00:00:00
 639 dhcpStatements: fixed-address hostname.intern
 640 </pre></blockquote>
 641
 642 </p>One could even add the LTSP configuration associated with a given
 643 machine, as long as the required attributes are available in a
 644 auxiliary object class.</p>
 645 </div>
 646   <div class="tags">
 647
 648
 649
 650    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 651
 652   </div>
 653  </div>
 654  <div class="padding"></div>
 655
 656  <div class="entry">
 657   <div class="title"><a href="http://people.skolelinux.org/pere/blog/Combining_PowerDNS_and_ISC_DHCP_LDAP_objects.html">Combining PowerDNS and ISC DHCP LDAP objects</a></div>
 658   <div class="date">2010-07-14 23:45</div>
 659   <div class="body">
 660 <p>For a while now, I have wanted to find a way to change the DNS and
 661 DHCP services in Debian Edu to use the same LDAP objects for a given
 662 computer, to avoid the possibility of having a inconsistent state for
 663 a computer in LDAP (as in DHCP but no DNS entry or the other way
 664 around) and make it easier to add computers to LDAP.</p>
 665
 666 <p>I've looked at how powerdns and dhcpd is using LDAP, and using this
 667 information finally found a solution that seem to work.</p>
 668
 669 <p>The old setup required three LDAP objects for a given computer.
 670 One forward DNS entry, one reverse DNS entry and one DHCP entry.  If
 671 we switch powerdns to use its strict LDAP method (ldap-method=strict
 672 in pdns-debian-edu.conf), the forward and reverse DNS entries are
 673 merged into one while making it impossible to transfer the reverse map
 674 to a slave DNS server.</p>
 675
 676 <p>If we also replace the object class used to get the DNS related
 677 attributes to one allowing these attributes to be combined with the
 678 dhcphost object class, we can merge the DNS and DHCP entries into one.
 679 I've written such object class in the dnsdomainaux.schema file (need
 680 proper OIDs, but that is a minor issue), and tested the setup.  It
 681 seem to work.</p>
 682
 683 <p>With this test setup in place, we can get away with one LDAP object
 684 for both DNS and DHCP, and even the LTSP configuration I suggested in
 685 an earlier email.  The combined LDAP object will look something like
 686 this:</p>
 687
 688 <blockquote><pre>
 689   dn: cn=hostname,cn=group1,cn=THINCLIENTS,cn=DHCP Config,dc=skole,dc=skolelinux,dc=no
 690   cn: hostname
 691   objectClass: dhcphost
 692   objectclass: domainrelatedobject
 693   objectclass: dnsdomainaux
 694   associateddomain: hostname.intern
 695   arecord: 10.11.12.13
 696   dhcphwaddress: ethernet 00:00:00:00:00:00
 697   dhcpstatements: fixed-address hostname
 698   ldapconfigsound: Y
 699 </pre></blockquote>
 700
 701 <p>The DNS server uses the associateddomain and arecord entries, while
 702 the DHCP server uses the dhcphwaddress and dhcpstatements entries
 703 before asking DNS to resolve the fixed-adddress.  LTSP will use
 704 dhcphwaddress or associateddomain and the ldapconfig* attributes.</p>
 705
 706 <p>I am not yet sure if I can get the DHCP server to look for its
 707 dhcphost in a different location, to allow us to put the objects
 708 outside the "DHCP Config" subtree, but hope to figure out a way to do
 709 that.  If I can't figure out a way to do that, we can still get rid of
 710 the hosts subtree and move all its content into the DHCP Config tree
 711 (which probably should be renamed to be more related to the new
 712 content.  I suspect cn=dnsdhcp,ou=services or something like that
 713 might be a good place to put it.</p>
 714
 715 <p>If you want to help out with implementing this for Debian Edu,
 716 please contact us on debian-edu@lists.debian.org.</p>
 717 </div>
 718   <div class="tags">
 719
 720
 721
 722    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 723
 724   </div>
 725  </div>
 726  <div class="padding"></div>
 727
 728  <div class="entry">
 729   <div class="title"><a href="http://people.skolelinux.org/pere/blog/Idea_for_storing_LTSP_configuration_in_LDAP.html">Idea for storing LTSP configuration in LDAP</a></div>
 730   <div class="date">2010-07-11 22:00</div>
 731   <div class="body">
 732 <p>Vagrant mentioned on IRC today that ltsp_config now support
 733 sourcing files from /usr/share/ltsp/ltsp_config.d/ on the thin
 734 clients, and that this can be used to fetch configuration from LDAP if
 735 Debian Edu choose to store configuration there.</p>
 736
 737 <p>Armed with this information, I got inspired and wrote a test module
 738 to get configuration from LDAP.  The idea is to look up the MAC
 739 address of the client in LDAP, and look for attributes on the form
 740 ltspconfigsetting=value, and use this to export SETTING=value to the
 741 LTSP clients.</p>
 742
 743 <p>The goal is to be able to store the LTSP configuration attributes
 744 in a "computer" LDAP object used by both DNS and DHCP, and thus
 745 allowing us to store all information about a computer in one place.</p>
 746
 747 <p>This is a untested draft implementation, and I welcome feedback on
 748 this approach.  A real LDAP schema for the ltspClientAux objectclass
 749 need to be written.  Comments, suggestions, etc?</p>
 750
 751 <blockquote><pre>
 752 # Store in /opt/ltsp/$arch/usr/share/ltsp/ltsp_config.d/ldap-config
 753 #
 754 # Fetch LTSP client settings from LDAP based on MAC address
 755 #
 756 # Uses ethernet address as stored in the dhcpHost objectclass using
 757 # the dhcpHWAddress attribute or ethernet address stored in the
 758 # ieee802Device objectclass with the macAddress attribute.
 759 #
 760 # This module is written to be schema agnostic, and only depend on the
 761 # existence of attribute names.
 762 #
 763 # The LTSP configuration variables are saved directly using a
 764 # ltspConfig prefix and uppercasing the rest of the attribute name.
 765 # To set the SERVER variable, set the ltspConfigServer attribute.
 766 #
 767 # Some LDAP schema should be created with all the relevant
 768 # configuration settings.  Something like this should work:
 769 #
 770 # objectclass ( 1.1.2.2 NAME 'ltspClientAux'
 771 #     SUP top
 772 #     AUXILIARY
 773 #     MAY ( ltspConfigServer $ ltsConfigSound $ ... )
 774
 775 LDAPSERVER=$(debian-edu-ldapserver)
 776 if [ "$LDAPSERVER" ] ; then
 777     LDAPBASE=$(debian-edu-ldapserver -b)
 778     for MAC in $(LANG=C ifconfig |grep -i hwaddr| awk '{print $5}'|sort -u) ; do
 779         filter="(|(dhcpHWAddress=ethernet $MAC)(macAddress=$MAC))"
 780         ldapsearch -h "$LDAPSERVER" -b "$LDAPBASE" -v -x "$filter" | \
 781             grep '^ltspConfig' | while read attr value ; do
 782             # Remove prefix and convert to upper case
 783             attr=$(echo $attr | sed 's/^ltspConfig//i' | tr a-z A-Z)
 784             # bass value on to clients
 785             eval "$attr=$value; export $attr"
 786         done
 787     done
 788 fi
 789 </pre></blockquote>
 790
 791 <p>I'm not sure this shell construction will work, because I suspect
 792 the while block might end up in a subshell causing the variables set
 793 there to not show up in ltsp-config, but if that is the case I am sure
 794 the code can be restructured to make sure the variables are passed on.
 795 I expect that can be solved with some testing. :)</p>
 796
 797 <p>If you want to help out with implementing this for Debian Edu,
 798 please contact us on debian-edu@lists.debian.org.</p>
 799
 800 <p>Update 2010-07-17: I am aware of another effort to store LTSP
 801 configuration in LDAP that was created around year 2000 by
 802 <a href="http://www.pcxperience.com/thinclient/documentation/ldap.html">PC
 803 Xperience, Inc., 2000</a>.  I found its
 804 <a href="http://people.redhat.com/alikins/ltsp/ldap/">files</a> on a
 805 personal home page over at redhat.com.</p>
 806 </div>
 807   <div class="tags">
 808
 809
 810
 811    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 812
 813   </div>
 814  </div>
 815  <div class="padding"></div>
 816
 817  <div class="entry">
 818   <div class="title"><a href="http://people.skolelinux.org/pere/blog/jXplorer__a_very_nice_LDAP_GUI.html">jXplorer, a very nice LDAP GUI</a></div>
 819   <div class="date">2010-07-09 12:55</div>
 820   <div class="body">
 821 <p>Since
 822 <a href="http://people.skolelinux.org/pere/blog/LUMA__a_very_nice_LDAP_GUI.html">my
 823 last post</a> about available LDAP tools in Debian, I was told about a
 824 LDAP GUI that is even better than luma.  The java application
 825 <a href="http://jxplorer.org/">jXplorer</a> is claimed to be capable of
 826 moving LDAP objects and subtrees using drag-and-drop, and can
 827 authenticate using Kerberos.  I have only tested the Kerberos
 828 authentication, but do not have a LDAP setup allowing me to rewrite
 829 LDAP with my test user yet.  It is
 830 <a href="http://packages.qa.debian.org/j/jxplorer.html">available in
 831 Debian</a> testing and unstable at the moment.  The only problem I
 832 have with it is how it handle errors.  If something go wrong, its
 833 non-intuitive behaviour require me to go through some query work list
 834 and remove the failing query.  Nothing big, but very annoying.</p>
 835 </div>
 836   <div class="tags">
 837
 838
 839
 840    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap</a>, <a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug</a>.
 841
 842   </div>
 843  </div>
 844  <div class="padding"></div>
 845
 846  <div class="entry">
 847   <div class="title"><a href="http://people.skolelinux.org/pere/blog/MS_Word_kr__ller_det_til_for_politiet_.html">MS Word krøller det til for politiet?</a></div>
 848   <div class="date">2010-07-08 14:00</div>
 849   <div class="body">
 850 <p>De siste dagene har Aftenposten
 851 <a href="http://www.aftenposten.no/nyheter/iriks/article3718597.ece">fortalt</a>
 852 <a href="http://www.aftenposten.no/nyheter/iriks/article3724249.ece">hvordan</a>
 853 politet har brukt skriveverktøy som ikke håndterer arabisk tekst og
 854 tekst som skal skrives fra høyre mot venstre når de har laget
 855 løpeseddel for å be om informasjon fra publikum.  Resultatet har vært
 856 en uleselig arabisk-bit på løpeseddelen.  Feilen har oppstått når
 857 teksten har blitt "kopiert inn i programvare som ikke har støtte for
 858 språk som skrives fra høyre mot venstre", og jeg er ganske sikker på
 859 at det er snakk om Microsoft Office i dette tilfellet.  Er det slik at
 860 MS Office i norsk språkdrakt ikke har støtte for tekst som skal
 861 skrives fra høyre mot venstre?  Jeg tror alle utgaver av
 862 OpenOffice.org har slik støtte, og det er jo ikke veldig vanskelig å
 863 la slik støtte finnes i alle utgaver av et program hvis støtten først
 864 er utviklet.  Aftenpostens melding får meg til å undre om problemet
 865 ville vært unngått hvis politiet brukte OpenOffice.org i stedet for MS
 866 Office.</p>
 867
 868 <p>Mon tro om det er flere eksempler på at MS Office har ødelagt for
 869 offentlig myndighet?</p>
 870 </div>
 871   <div class="tags">
 872
 873
 874
 875    Tags: <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>.
 876
 877   </div>
 878  </div>
 879  <div class="padding"></div>
 880
 881  <p style="text-align: right;"><a href="index.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS feed" width="36" height="14"></a></p>
 882
 883 <div id="sidebar">
 884
 885
 886
 887
 888
 889 <h2>Archive</h2>
 890 <ul>
 891
 892 <li>2010
 893 <ul>
 894
 895 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 896
 897 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 898
 899 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 900
 901 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 902
 903 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 904
 905 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 906
 907 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 908
 909 </ul></li>
 910
 911 <li>2009
 912 <ul>
 913
 914 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 915
 916 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 917
 918 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 919
 920 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 921
 922 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 923
 924 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 925
 926 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 927
 928 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 929
 930 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 931
 932 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 933
 934 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 935
 936 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 937
 938 </ul></li>
 939
 940 <li>2008
 941 <ul>
 942
 943 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 944
 945 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 946
 947 </ul></li>
 948
 949 </ul>
 950
 951
 952
 953 <h2>Tags</h2>
 954 <ul>
 955
 956  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (11)</a></li>
 957
 958  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 959
 960  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 961
 962  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (10)</a></li>
 963
 964  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (35)</a></li>
 965
 966  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (36)</a></li>
 967
 968  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (51)</a></li>
 969
 970  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (1)</a></li>
 971
 972  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (8)</a></li>
 973
 974  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (3)</a></li>
 975
 976  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (8)</a></li>
 977
 978  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (1)</a></li>
 979
 980  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 981
 982  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (5)</a></li>
 983
 984  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (71)</a></li>
 985
 986  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (88)</a></li>
 987
 988  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (14)</a></li>
 989
 990  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (14)</a></li>
 991
 992  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (10)</a></li>
 993
 994  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 995
 996  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (10)</a></li>
 997
 998  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (3)</a></li>
 999
1000  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (13)</a></li>
1001
1002  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (1)</a></li>
1003
1004  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (10)</a></li>
1005
1006  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (1)</a></li>
1007
1008  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (7)</a></li>
1009
1010 </ul>
1011
1012 </div>
1013
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