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  13     <div class="title">
  14  <h1>
  15      <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  16
  17  </h1>
  18
  19 </div>
  20
  21
  22     <h3>Entries from September 2014.</h3>
  23
  24     <div class="entry">
  25       <div class="title">
  26         <a href="http://people.skolelinux.org/pere/blog/Speeding_up_the_Debian_installer_using_eatmydata_and_dpkg_divert.html">Speeding up the Debian installer using eatmydata and dpkg-divert</a>
  27       </div>
  28       <div class="date">
  29         16th September 2014
  30       </div>
  31       <div class="body">
  32         <p>The <a href="https://www.debian.org/">Debian</a> installer could be
  33 a lot quicker.  When we install more than 2000 packages in
  34 <a href="http://www.skolelinux.org/">Skolelinux / Debian Edu</a> using
  35 tasksel in the installer, unpacking the binary packages take forever.
  36 A part of the slow I/O issue was discussed in
  37 <a href="https://bugs.debian.org/613428">bug #613428</a> about too
  38 much file system sync-ing done by dpkg, which is the package
  39 responsible for unpacking the binary packages.  Other parts (like code
  40 executed by postinst scripts) might also sync to disk during
  41 installation.  All this sync-ing to disk do not really make sense to
  42 me.  If the machine crash half-way through, I start over, I do not try
  43 to salvage the half installed system.  So the failure sync-ing is
  44 supposed to protect against, hardware or system crash, is not really
  45 relevant while the installer is running.</p>
  46
  47 <p>A few days ago, I thought of a way to get rid of all the file
  48 system sync()-ing in a fairly non-intrusive way, without the need to
  49 change the code in several packages.  The idea is not new, but I have
  50 not heard anyone propose the approach using dpkg-divert before.  It
  51 depend on the small and clever package
  52 <a href="https://packages.qa.debian.org/eatmydata">eatmydata</a>, which
  53 uses LD_PRELOAD to replace the system functions for syncing data to
  54 disk with functions doing nothing, thus allowing programs to live
  55 dangerous while speeding up disk I/O significantly.  Instead of
  56 modifying the implementation of dpkg, apt and tasksel (which are the
  57 packages responsible for selecting, fetching and installing packages),
  58 it occurred to me that we could just divert the programs away, replace
  59 them with a simple shell wrapper calling
  60 "eatmydata&nbsp;$program&nbsp;$@", to get the same effect.
  61 Yesterday I decided to test the idea, and wrapped up a simple
  62 implementation for the Debian Edu udeb.</p>
  63
  64 <p>The effect was stunning.  In my first test it reduced the running
  65 time of the pkgsel step (installing tasks) from 64 to less than 44
  66 minutes (20 minutes shaved off the installation) on an old Dell
  67 Latitude D505 machine.  I am not quite sure what the optimised time
  68 would have been, as I messed up the testing a bit, causing the debconf
  69 priority to get low enough for two questions to pop up during
  70 installation.  As soon as I saw the questions I moved the installation
  71 along, but do not know how long the question were holding up the
  72 installation.  I did some more measurements using Debian Edu Jessie,
  73 and got these results.  The time measured is the time stamp in
  74 /var/log/syslog between the "pkgsel: starting tasksel" and the
  75 "pkgsel: finishing up" lines, if you want to do the same measurement
  76 yourself.  In Debian Edu, the tasksel dialog do not show up, and the
  77 timing thus do not depend on how quickly the user handle the tasksel
  78 dialog.</p>
  79
  80 <p><table>
  81
  82 <tr>
  83 <th>Machine/setup</th>
  84 <th>Original tasksel</th>
  85 <th>Optimised tasksel</th>
  86 <th>Reduction</th>
  87 </tr>
  88
  89 <tr>
  90 <td>Latitude D505 Main+LTSP LXDE</td>
  91 <td>64 min (07:46-08:50)</td>
  92 <td><44 min (11:27-12:11)</td>
  93 <td>>20 min 18%</td>
  94 </tr>
  95
  96 <tr>
  97 <td>Latitude D505 Roaming LXDE</td>
  98 <td>57 min (08:48-09:45)</td>
  99 <td>34 min (07:43-08:17)</td>
 100 <td>23 min 40%</td>
 101 </tr>
 102
 103 <tr>
 104 <td>Latitude D505 Minimal</td>
 105 <td>22 min (10:37-10:59)</td>
 106 <td>11 min (11:16-11:27)</td>
 107 <td>11 min 50%</td>
 108 </tr>
 109
 110 <tr>
 111 <td>Thinkpad X200 Minimal</td>
 112 <td>6 min (08:19-08:25)</td>
 113 <td>4 min (08:04-08:08)</td>
 114 <td>2 min 33%</td>
 115 </tr>
 116
 117 <tr>
 118 <td>Thinkpad X200 Roaming KDE</td>
 119 <td>19 min (09:21-09:40)</td>
 120 <td>15 min (10:25-10:40)</td>
 121 <td>4 min 21%</td>
 122 </tr>
 123
 124 </table></p>
 125
 126 <p>The test is done using a netinst ISO on a USB stick, so some of the
 127 time is spent downloading packages.  The connection to the Internet
 128 was 100Mbit/s during testing, so downloading should not be a
 129 significant factor in the measurement.  Download typically took a few
 130 seconds to a few minutes, depending on the amount of packages being
 131 installed.</p>
 132
 133 <p>The speedup is implemented by using two hooks in
 134 <a href="https://www.debian.org/devel/debian-installer/">Debian
 135 Installer</a>, the pre-pkgsel.d hook to set up the diverts, and the
 136 finish-install.d hook to remove the divert at the end of the
 137 installation.  I picked the pre-pkgsel.d hook instead of the
 138 post-base-installer.d hook because I test using an ISO without the
 139 eatmydata package included, and the post-base-installer.d hook in
 140 Debian Edu can only operate on packages included in the ISO.  The
 141 negative effect of this is that I am unable to activate this
 142 optimization for the kernel installation step in d-i.  If the code is
 143 moved to the post-base-installer.d hook, the speedup would be larger
 144 for the entire installation.</p>
 145
 146 <p>I've implemented this in the
 147 <a href="https://packages.qa.debian.org/debian-edu-install">debian-edu-install</a>
 148 git repository, and plan to provide the optimization as part of the
 149 Debian Edu installation.  If you want to test this yourself, you can
 150 create two files in the installer (or in an udeb).  One shell script
 151 need do go into /usr/lib/pre-pkgsel.d/, with content like this:</p>
 152
 153 <p><blockquote><pre>
 154 #!/bin/sh
 155 set -e
 156 . /usr/share/debconf/confmodule
 157 info() {
 158     logger -t my-pkgsel "info: $*"
 159 }
 160 error() {
 161     logger -t my-pkgsel "error: $*"
 162 }
 163 override_install() {
 164     apt-install eatmydata || true
 165     if [ -x /target/usr/bin/eatmydata ] ; then
 166         for bin in dpkg apt-get aptitude tasksel ; do
 167             file=/usr/bin/$bin
 168             # Test that the file exist and have not been diverted already.
 169             if [ -f /target$file ] ; then
 170                 info "diverting $file using eatmydata"
 171                 printf "#!/bin/sh\neatmydata $bin.distrib \"\$@\"\n" \
 172                     > /target$file.edu
 173                 chmod 755 /target$file.edu
 174                 in-target dpkg-divert --package debian-edu-config \
 175                     --rename --quiet --add $file
 176                 ln -sf ./$bin.edu /target$file
 177             else
 178                 error "unable to divert $file, as it is missing."
 179             fi
 180         done
 181     else
 182         error "unable to find /usr/bin/eatmydata after installing the eatmydata pacage"
 183     fi
 184 }
 185
 186 override_install
 187 </pre></blockquote></p>
 188
 189 <p>To clean up, another shell script should go into
 190 /usr/lib/finish-install.d/ with code like this:
 191
 192 <p><blockquote><pre>
 193 #! /bin/sh -e
 194 . /usr/share/debconf/confmodule
 195 error() {
 196     logger -t my-finish-install "error: $@"
 197 }
 198 remove_install_override() {
 199     for bin in dpkg apt-get aptitude tasksel ; do
 200         file=/usr/bin/$bin
 201         if [ -x /target$file.edu ] ; then
 202             rm /target$file
 203             in-target dpkg-divert --package debian-edu-config \
 204                 --rename --quiet --remove $file
 205             rm /target$file.edu
 206         else
 207             error "Missing divert for $file."
 208         fi
 209     done
 210     sync # Flush file buffers before continuing
 211 }
 212
 213 remove_install_override
 214 </pre></blockquote></p>
 215
 216 <p>In Debian Edu, I placed both code fragments in a separate script
 217 edu-eatmydata-install and call it from the pre-pkgsel.d and
 218 finish-install.d scripts.</p>
 219
 220 <p>By now you might ask if this change should get into the normal
 221 Debian installer too?  I suspect it should, but am not sure the
 222 current debian-installer coordinators find it useful enough.  It also
 223 depend on the side effects of the change.  I'm not aware of any, but I
 224 guess we will see if the change is safe after some more testing.
 225 Perhaps there is some package in Debian depending on sync() and
 226 fsync() having effect?  Perhaps it should go into its own udeb, to
 227 allow those of us wanting to enable it to do so without affecting
 228 everyone.</p>
 229
 230       </div>
 231       <div class="tags">
 232
 233
 234         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>.
 235
 236
 237       </div>
 238     </div>
 239     <div class="padding"></div>
 240
 241     <div class="entry">
 242       <div class="title">
 243         <a href="http://people.skolelinux.org/pere/blog/Good_bye_subkeys_pgp_net__welcome_pool_sks_keyservers_net.html">Good bye subkeys.pgp.net, welcome pool.sks-keyservers.net</a>
 244       </div>
 245       <div class="date">
 246         10th September 2014
 247       </div>
 248       <div class="body">
 249         <p>Yesterday, I had the pleasure of attending a talk with the
 250 <a href="http://www.nuug.no/">Norwegian Unix User Group</a> about
 251 <a href="http://www.nuug.no/aktiviteter/20140909-sks-keyservers/">the
 252 OpenPGP keyserver pool sks-keyservers.net</a>, and was very happy to
 253 learn that there is a large set of publicly available key servers to
 254 use when looking for peoples public key.  So far I have used
 255 subkeys.pgp.net, and some times wwwkeys.nl.pgp.net when the former
 256 were misbehaving, but those days are ended.  The servers I have used
 257 up until yesterday have been slow and some times unavailable.  I hope
 258 those problems are gone now.</p>
 259
 260 <p>Behind the round robin DNS entry of the
 261 <a href="https://sks-keyservers.net/">sks-keyservers.net</a> service
 262 there is a pool of more than 100 keyservers which are checked every
 263 day to ensure they are well connected and up to date.  It must be
 264 better than what I have used so far. :)</p>
 265
 266 <p>Yesterdays speaker told me that the service is the default
 267 keyserver provided by the default configuration in GnuPG, but this do
 268 not seem to be used in Debian.  Perhaps it should?</p>
 269
 270 <p>Anyway, I've updated my ~/.gnupg/options file to now include this
 271 line:</p>
 272
 273 <p><blockquote><pre>
 274 keyserver pool.sks-keyservers.net
 275 </pre></blockquote></p>
 276
 277 <p>With GnuPG version 2 one can also locate the keyserver using SRV
 278 entries in DNS.  Just for fun, I did just that at work, so now every
 279 user of GnuPG at the University of Oslo should find a OpenGPG
 280 keyserver automatically should their need it:</p>
 281
 282 <p><blockquote><pre>
 283 % host -t srv _pgpkey-http._tcp.uio.no
 284 _pgpkey-http._tcp.uio.no has SRV record 0 100 11371 pool.sks-keyservers.net.
 285 %
 286 </pre></blockquote></p>
 287
 288 <p>Now if only
 289 <a href="http://ietfreport.isoc.org/idref/draft-shaw-openpgp-hkp/">the
 290 HKP lookup protocol</a> supported finding signature paths, I would be
 291 very happy.  It can look up a given key or search for a user ID, but I
 292 normally do not want that, but to find a trust path from my key to
 293 another key.  Given a user ID or key ID, I would like to find (and
 294 download) the keys representing a signature path from my key to the
 295 key in question, to be able to get a trust path between the two keys.
 296 This is as far as I can tell not possible today.  Perhaps something
 297 for a future version of the protocol?</p>
 298
 299       </div>
 300       <div class="tags">
 301
 302
 303         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/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>.
 304
 305
 306       </div>
 307     </div>
 308     <div class="padding"></div>
 309
 310     <p style="text-align: right;"><a href="09.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS Feed" width="36" height="14" /></a></p>
 311     <div id="sidebar">
 312
 313
 314
 315 <h2>Archive</h2>
 316 <ul>
 317
 318 <li>2014
 319 <ul>
 320
 321 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
 322
 323 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
 324
 325 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
 326
 327 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
 328
 329 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
 330
 331 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
 332
 333 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
 334
 335 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
 336
 337 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/09/">September (2)</a></li>
 338
 339 </ul></li>
 340
 341 <li>2013
 342 <ul>
 343
 344 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 345
 346 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 347
 348 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 349
 350 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 351
 352 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 353
 354 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 355
 356 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 357
 358 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 359
 360 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 361
 362 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 363
 364 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
 365
 366 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
 367
 368 </ul></li>
 369
 370 <li>2012
 371 <ul>
 372
 373 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
 374
 375 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
 376
 377 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
 378
 379 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
 380
 381 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
 382
 383 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
 384
 385 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
 386
 387 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
 388
 389 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
 390
 391 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
 392
 393 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
 394
 395 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
 396
 397 </ul></li>
 398
 399 <li>2011
 400 <ul>
 401
 402 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 403
 404 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 405
 406 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
 407
 408 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
 409
 410 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
 411
 412 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
 413
 414 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
 415
 416 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
 417
 418 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
 419
 420 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
 421
 422 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
 423
 424 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
 425
 426 </ul></li>
 427
 428 <li>2010
 429 <ul>
 430
 431 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 432
 433 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 434
 435 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 436
 437 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 438
 439 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 440
 441 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 442
 443 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 444
 445 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
 446
 447 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
 448
 449 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
 450
 451 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
 452
 453 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
 454
 455 </ul></li>
 456
 457 <li>2009
 458 <ul>
 459
 460 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 461
 462 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 463
 464 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 465
 466 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 467
 468 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 469
 470 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 471
 472 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 473
 474 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 475
 476 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 477
 478 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 479
 480 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 481
 482 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 483
 484 </ul></li>
 485
 486 <li>2008
 487 <ul>
 488
 489 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 490
 491 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 492
 493 </ul></li>
 494
 495 </ul>
 496
 497
 498
 499 <h2>Tags</h2>
 500 <ul>
 501
 502  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
 503
 504  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 505
 506  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 507
 508  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
 509
 510  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (8)</a></li>
 511
 512  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (14)</a></li>
 513
 514  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
 515
 516  <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
 517
 518  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (101)</a></li>
 519
 520  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (149)</a></li>
 521
 522  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
 523
 524  <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (15)</a></li>
 525
 526  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (12)</a></li>
 527
 528  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
 529
 530  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (253)</a></li>
 531
 532  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (21)</a></li>
 533
 534  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
 535
 536  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (13)</a></li>
 537
 538  <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (8)</a></li>
 539
 540  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (11)</a></li>
 541
 542  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (41)</a></li>
 543
 544  <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (9)</a></li>
 545
 546  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (18)</a></li>
 547
 548  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
 549
 550  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
 551
 552  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 553
 554  <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
 555
 556  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (29)</a></li>
 557
 558  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (247)</a></li>
 559
 560  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (162)</a></li>
 561
 562  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (11)</a></li>
 563
 564  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
 565
 566  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (48)</a></li>
 567
 568  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (74)</a></li>
 569
 570  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
 571
 572  <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
 573
 574  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
 575
 576  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (2)</a></li>
 577
 578  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (9)</a></li>
 579
 580  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 581
 582  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
 583
 584  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
 585
 586  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (41)</a></li>
 587
 588  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
 589
 590  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (4)</a></li>
 591
 592  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (45)</a></li>
 593
 594  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (3)</a></li>
 595
 596  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (9)</a></li>
 597
 598  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (25)</a></li>
 599
 600  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (1)</a></li>
 601
 602  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (8)</a></li>
 603
 604  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (43)</a></li>
 605
 606  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
 607
 608  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (33)</a></li>
 609
 610 </ul>
 611
 612
 613     </div>
 614     <p style="text-align: right">
 615  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
 616 </p>
 617
 618   </body>
 619 </html>