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   6     <title>Petter Reinholdtsen</title>
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  12     <div class="title">
  13  <h1>
  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/Some_notes_on_fault_tolerant_storage_systems.html">Some notes on fault tolerant storage systems</a></div>
  24       <div class="date"> 1st November 2017</div>
  25       <div class="body"><p>If you care about how fault tolerant your storage is, you might
  26 find these articles and papers interesting.  They have formed how I
  27 think of when designing a storage system.</p>
  28
  29 <ul>
  30
  31 <li>USENIX :login; <a
  32 href="https://www.usenix.org/publications/login/summer2017/ganesan">Redundancy
  33 Does Not Imply Fault Tolerance.  Analysis of Distributed Storage
  34 Reactions to Single Errors and Corruptions</a> by Aishwarya Ganesan,
  35 Ramnatthan Alagappan, Andrea C. Arpaci-Dusseau, and Remzi
  36 H. Arpaci-Dusseau</li>
  37
  38 <li>ZDNet
  39 <a href="http://www.zdnet.com/article/why-raid-5-stops-working-in-2009/">Why
  40 RAID 5 stops working in 2009</a> by Robin Harris</li>
  41
  42 <li>ZDNet
  43 <a href="http://www.zdnet.com/article/why-raid-6-stops-working-in-2019/">Why
  44 RAID 6 stops working in 2019</a> by Robin Harris</li>
  45
  46 <li>USENIX FAST'07
  47 <a href="http://research.google.com/archive/disk_failures.pdf">Failure
  48 Trends in a Large Disk Drive Population</a> by Eduardo Pinheiro,
  49 Wolf-Dietrich Weber and Luiz André Barroso</li>
  50
  51 <li>USENIX ;login: <a
  52 href="https://www.usenix.org/system/files/login/articles/hughes12-04.pdf">Data
  53 Integrity.  Finding Truth in a World of Guesses and Lies</a> by Doug
  54 Hughes</li>
  55
  56 <li>USENIX FAST'08
  57 <a href="https://www.usenix.org/events/fast08/tech/full_papers/bairavasundaram/bairavasundaram_html/">An
  58 Analysis of Data Corruption in the Storage Stack</a> by
  59 L. N. Bairavasundaram, G. R. Goodson, B. Schroeder, A. C.
  60 Arpaci-Dusseau, and R. H. Arpaci-Dusseau</li>
  61
  62 <li>USENIX FAST'07 <a
  63 href="https://www.usenix.org/legacy/events/fast07/tech/schroeder/schroeder_html/">Disk
  64 failures in the real world: what does an MTTF of 1,000,000 hours mean
  65 to you?</a> by B. Schroeder and G. A. Gibson.</li>
  66
  67 <li>USENIX ;login: <a
  68 href="https://www.usenix.org/events/fast08/tech/full_papers/jiang/jiang_html/">Are
  69 Disks the Dominant Contributor for Storage Failures?  A Comprehensive
  70 Study of Storage Subsystem Failure Characteristics</a> by Weihang
  71 Jiang, Chongfeng Hu, Yuanyuan Zhou, and Arkady Kanevsky</li>
  72
  73 <li>SIGMETRICS 2007
  74 <a href="http://research.cs.wisc.edu/adsl/Publications/latent-sigmetrics07.pdf">An
  75 analysis of latent sector errors in disk drives</a> by
  76 L. N. Bairavasundaram, G. R. Goodson, S. Pasupathy, and J. Schindler</li>
  77
  78 </ul>
  79
  80 <p>Several of these research papers are based on data collected from
  81 hundred thousands or millions of disk, and their findings are eye
  82 opening.  The short story is simply do not implicitly trust RAID or
  83 redundant storage systems.  Details matter.  And unfortunately there
  84 are few options on Linux addressing all the identified issues.  Both
  85 ZFS and Btrfs are doing a fairly good job, but have legal and
  86 practical issues on their own.  I wonder how cluster file systems like
  87 Ceph do in this regard.  After all, there is an old saying, you know
  88 you have a distributed system when the crash of a compyter you have
  89 never heard of stops you from getting any work done.  The same holds
  90 true if fault tolerance do not work.</p>
  91
  92 <p>Just remember, in the end, it do not matter how redundant, or how
  93 fault tolerant your storage is, if you do not continuously monitor its
  94 status to detect and replace failed disks.</p>
  95 </div>
  96       <div class="tags">
  97
  98
  99         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/raid">raid</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin</a>.
 100
 101
 102       </div>
 103     </div>
 104     <div class="padding"></div>
 105
 106     <div class="entry">
 107       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Web_services_for_writing_academic_LaTeX_papers_as_a_team.html">Web services for writing academic LaTeX papers as a team</a></div>
 108       <div class="date">31st October 2017</div>
 109       <div class="body"><p>I was surprised today to learn that a friend in academia did not
 110 know there are easily available web services available for writing
 111 LaTeX documents as a team.  I thought it was common knowledge, but to
 112 make sure at least my readers are aware of it, I would like to mention
 113 these useful services for writing LaTeX documents.  Some of them even
 114 provide a WYSIWYG editor to ease writing even further.</p>
 115
 116 <p>There are two commercial services available,
 117 <a href="https://sharelatex.com">ShareLaTeX</a> and
 118 <a href="https://overleaf.com">Overleaf</a>.  They are very easy to
 119 use.  Just start a new document, select which publisher to write for
 120 (ie which LaTeX style to use), and start writing.  Note, these two
 121 have announced their intention to join forces, so soon it will only be
 122 one joint service.  I've used both for different documents, and they
 123 work just fine.  While
 124 <a href="https://github.com/sharelatex/sharelatex">ShareLaTeX is free
 125 software</a>, while the latter is not.  According to <a
 126 href="https://www.overleaf.com/help/17-is-overleaf-open-source">a
 127 announcement from Overleaf</a>, they plan to keep the ShareLaTeX code
 128 base maintained as free software.</p>
 129
 130 But these two are not the only alternatives.
 131 <a href="https://app.fiduswriter.org/">Fidus Writer</a> is another free
 132 software solution with <a href="https://github.com/fiduswriter">the
 133 source available on github</a>.  I have not used it myself.  Several
 134 others can be found on the nice
 135 <a href="https://alternativeto.net/software/sharelatex/">alterntiveTo
 136 web service</a>.
 137
 138 <p>If you like Google Docs or Etherpad, but would like to write
 139 documents in LaTeX, you should check out these services.  You can even
 140 host your own, if you want to. :)</p>
 141
 142 </div>
 143       <div class="tags">
 144
 145
 146         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 147
 148
 149       </div>
 150     </div>
 151     <div class="padding"></div>
 152
 153     <div class="entry">
 154       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Locating_IMDB_IDs_of_movies_in_the_Internet_Archive_using_Wikidata.html">Locating IMDB IDs of movies in the Internet Archive using Wikidata</a></div>
 155       <div class="date">25th October 2017</div>
 156       <div class="body"><p>Recently, I needed to automatically check the copyright status of a
 157 set of <a href="http://www.imdb.com/">The Internet Movie database
 158 (IMDB)</a> entries, to figure out which one of the movies they refer
 159 to can be freely distributed on the Internet.  This proved to be
 160 harder than it sounds.  IMDB for sure list movies without any
 161 copyright protection, where the copyright protection has expired or
 162 where the movie is lisenced using a permissive license like one from
 163 Creative Commons.  These are mixed with copyright protected movies,
 164 and there seem to be no way to separate these classes of movies using
 165 the information in IMDB.</p>
 166
 167 <p>First I tried to look up entries manually in IMDB,
 168 <a href="https://www.wikipedia.org/">Wikipedia</a> and
 169 <a href="https://www.archive.org/">The Internet Archive</a>, to get a
 170 feel how to do this.  It is hard to know for sure using these sources,
 171 but it should be possible to be reasonable confident a movie is "out
 172 of copyright" with a few hours work per movie.  As I needed to check
 173 almost 20,000 entries, this approach was not sustainable.  I simply
 174 can not work around the clock for about 6 years to check this data
 175 set.</p>
 176
 177 <p>I asked the people behind The Internet Archive if they could
 178 introduce a new metadata field in their metadata XML for IMDB ID, but
 179 was told that they leave it completely to the uploaders to update the
 180 metadata.  Some of the metadata entries had IMDB links in the
 181 description, but I found no way to download all metadata files in bulk
 182 to locate those ones and put that approach aside.</p>
 183
 184 <p>In the process I noticed several Wikipedia articles about movies
 185 had links to both IMDB and The Internet Archive, and it occured to me
 186 that I could use the Wikipedia RDF data set to locate entries with
 187 both, to at least get a lower bound on the number of movies on The
 188 Internet Archive with a IMDB ID.  This is useful based on the
 189 assumption that movies distributed by The Internet Archive can be
 190 legally distributed on the Internet.  With some help from the RDF
 191 community (thank you DanC), I was able to come up with this query to
 192 pass to <a href="https://query.wikidata.org/">the SPARQL interface on
 193 Wikidata</a>:
 194
 195 <p><pre>
 196 SELECT ?work ?imdb ?ia ?when ?label
 197 WHERE
 198 {
 199   ?work wdt:P31/wdt:P279* wd:Q11424.
 200   ?work wdt:P345 ?imdb.
 201   ?work wdt:P724 ?ia.
 202   OPTIONAL {
 203         ?work wdt:P577 ?when.
 204         ?work rdfs:label ?label.
 205         FILTER(LANG(?label) = "en").
 206   }
 207 }
 208 </pre></p>
 209
 210 <p>If I understand the query right, for every film entry anywhere in
 211 Wikpedia, it will return the IMDB ID and The Internet Archive ID, and
 212 when the movie was released and its English title, if either or both
 213 of the latter two are available.  At the moment the result set contain
 214 2338 entries.  Of course, it depend on volunteers including both
 215 correct IMDB and The Internet Archive IDs in the wikipedia articles
 216 for the movie.  It should be noted that the result will include
 217 duplicates if the movie have entries in several languages.  There are
 218 some bogus entries, either because The Internet Archive ID contain a
 219 typo or because the movie is not available from The Internet Archive.
 220 I did not verify the IMDB IDs, as I am unsure how to do that
 221 automatically.</p>
 222
 223 <p>I wrote a small python script to extract the data set from Wikidata
 224 and check if the XML metadata for the movie is available from The
 225 Internet Archive, and after around 1.5 hour it produced a list of 2097
 226 free movies and their IMDB ID.  In total, 171 entries in Wikidata lack
 227 the refered Internet Archive entry.  I assume the 70 "disappearing"
 228 entries (ie 2338-2097-171) are duplicate entries.</p>
 229
 230 <p>This is not too bad, given that The Internet Archive report to
 231 contain <a href="https://archive.org/details/feature_films">5331
 232 feature films</a> at the moment, but it also mean more than 3000
 233 movies are missing on Wikipedia or are missing the pair of references
 234 on Wikipedia.</p>
 235
 236 <p>I was curious about the distribution by release year, and made a
 237 little graph to show how the amount of free movies is spread over the
 238 years:<p>
 239
 240 <p><img src="http://people.skolelinux.org/pere/blog/images/2017-10-25-verk-i-det-fri-filmer.png"></p>
 241
 242 <p>I expect the relative distribution of the remaining 3000 movies to
 243 be similar.</p>
 244
 245 <p>If you want to help, and want to ensure Wikipedia can be used to
 246 cross reference The Internet Archive and The Internet Movie Database,
 247 please make sure entries like this are listed under the "External
 248 links" heading on the Wikipedia article for the movie:</p>
 249
 250 <p><pre>
 251 * {{Internet Archive film|id=FightingLady}}
 252 * {{IMDb title|id=0036823|title=The Fighting Lady}}
 253 </pre></p>
 254
 255 <p>Please verify the links on the final page, to make sure you did not
 256 introduce a typo.</p>
 257
 258 <p>Here is the complete list, if you want to correct the 171
 259 identified Wikipedia entries with broken links to The Internet
 260 Archive: <a href="http://www.wikidata.org/entity/Q1140317">Q1140317</a>,
 261 <a href="http://www.wikidata.org/entity/Q458656">Q458656</a>,
 262 <a href="http://www.wikidata.org/entity/Q458656">Q458656</a>,
 263 <a href="http://www.wikidata.org/entity/Q470560">Q470560</a>,
 264 <a href="http://www.wikidata.org/entity/Q743340">Q743340</a>,
 265 <a href="http://www.wikidata.org/entity/Q822580">Q822580</a>,
 266 <a href="http://www.wikidata.org/entity/Q480696">Q480696</a>,
 267 <a href="http://www.wikidata.org/entity/Q128761">Q128761</a>,
 268 <a href="http://www.wikidata.org/entity/Q1307059">Q1307059</a>,
 269 <a href="http://www.wikidata.org/entity/Q1335091">Q1335091</a>,
 270 <a href="http://www.wikidata.org/entity/Q1537166">Q1537166</a>,
 271 <a href="http://www.wikidata.org/entity/Q1438334">Q1438334</a>,
 272 <a href="http://www.wikidata.org/entity/Q1479751">Q1479751</a>,
 273 <a href="http://www.wikidata.org/entity/Q1497200">Q1497200</a>,
 274 <a href="http://www.wikidata.org/entity/Q1498122">Q1498122</a>,
 275 <a href="http://www.wikidata.org/entity/Q865973">Q865973</a>,
 276 <a href="http://www.wikidata.org/entity/Q834269">Q834269</a>,
 277 <a href="http://www.wikidata.org/entity/Q841781">Q841781</a>,
 278 <a href="http://www.wikidata.org/entity/Q841781">Q841781</a>,
 279 <a href="http://www.wikidata.org/entity/Q1548193">Q1548193</a>,
 280 <a href="http://www.wikidata.org/entity/Q499031">Q499031</a>,
 281 <a href="http://www.wikidata.org/entity/Q1564769">Q1564769</a>,
 282 <a href="http://www.wikidata.org/entity/Q1585239">Q1585239</a>,
 283 <a href="http://www.wikidata.org/entity/Q1585569">Q1585569</a>,
 284 <a href="http://www.wikidata.org/entity/Q1624236">Q1624236</a>,
 285 <a href="http://www.wikidata.org/entity/Q4796595">Q4796595</a>,
 286 <a href="http://www.wikidata.org/entity/Q4853469">Q4853469</a>,
 287 <a href="http://www.wikidata.org/entity/Q4873046">Q4873046</a>,
 288 <a href="http://www.wikidata.org/entity/Q915016">Q915016</a>,
 289 <a href="http://www.wikidata.org/entity/Q4660396">Q4660396</a>,
 290 <a href="http://www.wikidata.org/entity/Q4677708">Q4677708</a>,
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 295 <a href="http://www.wikidata.org/entity/Q882066">Q882066</a>,
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 298 <a href="http://www.wikidata.org/entity/Q204191">Q204191</a>,
 299 <a href="http://www.wikidata.org/entity/Q1194170">Q1194170</a>,
 300 <a href="http://www.wikidata.org/entity/Q940014">Q940014</a>,
 301 <a href="http://www.wikidata.org/entity/Q946863">Q946863</a>,
 302 <a href="http://www.wikidata.org/entity/Q172837">Q172837</a>,
 303 <a href="http://www.wikidata.org/entity/Q573077">Q573077</a>,
 304 <a href="http://www.wikidata.org/entity/Q1219005">Q1219005</a>,
 305 <a href="http://www.wikidata.org/entity/Q1219599">Q1219599</a>,
 306 <a href="http://www.wikidata.org/entity/Q1643798">Q1643798</a>,
 307 <a href="http://www.wikidata.org/entity/Q1656352">Q1656352</a>,
 308 <a href="http://www.wikidata.org/entity/Q1659549">Q1659549</a>,
 309 <a href="http://www.wikidata.org/entity/Q1660007">Q1660007</a>,
 310 <a href="http://www.wikidata.org/entity/Q1698154">Q1698154</a>,
 311 <a href="http://www.wikidata.org/entity/Q1737980">Q1737980</a>,
 312 <a href="http://www.wikidata.org/entity/Q1877284">Q1877284</a>,
 313 <a href="http://www.wikidata.org/entity/Q1199354">Q1199354</a>,
 314 <a href="http://www.wikidata.org/entity/Q1199354">Q1199354</a>,
 315 <a href="http://www.wikidata.org/entity/Q1199451">Q1199451</a>,
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 317 <a href="http://www.wikidata.org/entity/Q1212179">Q1212179</a>,
 318 <a href="http://www.wikidata.org/entity/Q1238382">Q1238382</a>,
 319 <a href="http://www.wikidata.org/entity/Q4906454">Q4906454</a>,
 320 <a href="http://www.wikidata.org/entity/Q320219">Q320219</a>,
 321 <a href="http://www.wikidata.org/entity/Q1148649">Q1148649</a>,
 322 <a href="http://www.wikidata.org/entity/Q645094">Q645094</a>,
 323 <a href="http://www.wikidata.org/entity/Q5050350">Q5050350</a>,
 324 <a href="http://www.wikidata.org/entity/Q5166548">Q5166548</a>,
 325 <a href="http://www.wikidata.org/entity/Q2677926">Q2677926</a>,
 326 <a href="http://www.wikidata.org/entity/Q2698139">Q2698139</a>,
 327 <a href="http://www.wikidata.org/entity/Q2707305">Q2707305</a>,
 328 <a href="http://www.wikidata.org/entity/Q2740725">Q2740725</a>,
 329 <a href="http://www.wikidata.org/entity/Q2024780">Q2024780</a>,
 330 <a href="http://www.wikidata.org/entity/Q2117418">Q2117418</a>,
 331 <a href="http://www.wikidata.org/entity/Q2138984">Q2138984</a>,
 332 <a href="http://www.wikidata.org/entity/Q1127992">Q1127992</a>,
 333 <a href="http://www.wikidata.org/entity/Q1058087">Q1058087</a>,
 334 <a href="http://www.wikidata.org/entity/Q1070484">Q1070484</a>,
 335 <a href="http://www.wikidata.org/entity/Q1080080">Q1080080</a>,
 336 <a href="http://www.wikidata.org/entity/Q1090813">Q1090813</a>,
 337 <a href="http://www.wikidata.org/entity/Q1251918">Q1251918</a>,
 338 <a href="http://www.wikidata.org/entity/Q1254110">Q1254110</a>,
 339 <a href="http://www.wikidata.org/entity/Q1257070">Q1257070</a>,
 340 <a href="http://www.wikidata.org/entity/Q1257079">Q1257079</a>,
 341 <a href="http://www.wikidata.org/entity/Q1197410">Q1197410</a>,
 342 <a href="http://www.wikidata.org/entity/Q1198423">Q1198423</a>,
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 346 <a href="http://www.wikidata.org/entity/Q1171364">Q1171364</a>,
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 348 <a href="http://www.wikidata.org/entity/Q5166611">Q5166611</a>,
 349 <a href="http://www.wikidata.org/entity/Q5166611">Q5166611</a>,
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 352 <a href="http://www.wikidata.org/entity/Q7533269">Q7533269</a>,
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 409 <a href="http://www.wikidata.org/entity/Q18218448">Q18218448</a>,
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 429 <a href="http://www.wikidata.org/entity/Q3429733">Q3429733</a>,
 430 <a href="http://www.wikidata.org/entity/Q774474">Q774474</a></p>
 431 </div>
 432       <div class="tags">
 433
 434
 435         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett</a>.
 436
 437
 438       </div>
 439     </div>
 440     <div class="padding"></div>
 441
 442     <div class="entry">
 443       <div class="title"><a href="http://people.skolelinux.org/pere/blog/A_one_way_wall_on_the_border_.html">A one-way wall on the border?</a></div>
 444       <div class="date">14th October 2017</div>
 445       <div class="body"><p>I find it fascinating how many of the people being locked inside
 446 the proposed border wall between USA and Mexico support the idea.  The
 447 proposal to keep Mexicans out reminds me of
 448 <a href="http://www.history.com/news/10-things-you-may-not-know-about-the-berlin-wall">the
 449 propaganda twist from the East Germany government</a> calling the wall
 450 the “Antifascist Bulwark” after erecting the Berlin Wall, claiming
 451 that the wall was erected to keep enemies from creeping into East
 452 Germany, while it was obvious to the people locked inside it that it
 453 was erected to keep the people from escaping.</p>
 454
 455 <p>Do the people in USA supporting this wall really believe it is a
 456 one way wall, only keeping people on the outside from getting in,
 457 while not keeping people in the inside from getting out?</p>
 458 </div>
 459       <div class="tags">
 460
 461
 462         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 463
 464
 465       </div>
 466     </div>
 467     <div class="padding"></div>
 468
 469     <div class="entry">
 470       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Generating_3D_prints_in_Debian_using_Cura_and_Slic3r__prusa_.html">Generating 3D prints in Debian using Cura and Slic3r(-prusa)</a></div>
 471       <div class="date"> 9th October 2017</div>
 472       <div class="body"><p>At my nearby maker space,
 473 <a href="http://sonen.ifi.uio.no/">Sonen</a>, I heard the story that it
 474 was easier to generate gcode files for theyr 3D printers (Ultimake 2+)
 475 on Windows and MacOS X than Linux, because the software involved had
 476 to be manually compiled and set up on Linux while premade packages
 477 worked out of the box on Windows and MacOS X.  I found this annoying,
 478 as the software involved,
 479 <a href="https://github.com/Ultimaker/Cura">Cura</a>, is free software
 480 and should be trivial to get up and running on Linux if someone took
 481 the time to package it for the relevant distributions.  I even found
 482 <a href="https://bugs.debian.org/706656">a request for adding into
 483 Debian</a> from 2013, which had seem some activity over the years but
 484 never resulted in the software showing up in Debian.  So a few days
 485 ago I offered my help to try to improve the situation.</p>
 486
 487 <p>Now I am very happy to see that all the packages required by a
 488 working Cura in Debian are uploaded into Debian and waiting in the NEW
 489 queue for the ftpmasters to have a look.  You can track the progress
 490 on
 491 <a href="https://qa.debian.org/developer.php?email=3dprinter-general%40lists.alioth.debian.org">the
 492 status page for the 3D printer team</a>.</p>
 493
 494 <p>The uploaded packages are a bit behind upstream, and was uploaded
 495 now to get slots in <a href="https://ftp-master.debian.org/new.html">the NEW
 496 queue</a> while we work up updating the packages to the latest
 497 upstream version.</p>
 498
 499 <p>On a related note, two competitors for Cura, which I found harder
 500 to use and was unable to configure correctly for Ultimaker 2+ in the
 501 short time I spent on it, are already in Debian.  If you are looking
 502 for 3D printer "slicers" and want something already available in
 503 Debian, check out
 504 <a href="https://tracker.debian.org/pkg/slic3r">slic3r</a> and
 505 <a href="https://tracker.debian.org/pkg/slic3r-prusa">slic3r-prusa</a>.
 506 The latter is a fork of the former.</p>
 507 </div>
 508       <div class="tags">
 509
 510
 511         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer</a>, <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 512
 513
 514       </div>
 515     </div>
 516     <div class="padding"></div>
 517
 518     <div class="entry">
 519       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Mangler_du_en_skrue__eller_har_du_en_skrue_l_s_.html">Mangler du en skrue, eller har du en skrue løs?</a></div>
 520       <div class="date"> 4th October 2017</div>
 521       <div class="body">Når jeg holder på med ulike prosjekter, så trenger jeg stadig ulike
 522 skruer.  Det siste prosjektet jeg holder på med er å lage
 523 <a href="https://www.thingiverse.com/thing:676916">en boks til en
 524 HDMI-touch-skjerm</a> som skal brukes med Raspberry Pi.  Boksen settes
 525 sammen med skruer og bolter, og jeg har vært i tvil om hvor jeg kan
 526 få tak i de riktige skruene.  Clas Ohlson og Jernia i nærheten har
 527 sjelden hatt det jeg trenger.  Men her om dagen fikk jeg et fantastisk
 528 tips for oss som bor i Oslo.
 529 <a href="http://www.zachskruer.no/">Zachariassen Jernvare AS</a> i
 530 <a href="http://www.openstreetmap.org/?mlat=59.93421&mlon=10.76795#map=19/59.93421/10.76795">Hegermannsgate
 531 23A på Torshov</a> har et fantastisk utvalg, og åpent mellom 09:00 og
 532 17:00.  De selger skruer, muttere, bolter, skiver etc i løs vekt, og
 533 så langt har jeg fått alt jeg har lett etter.  De har i tillegg det
 534 meste av annen jernvare, som verktøy, lamper, ledninger, etc.  Jeg
 535 håper de har nok kunder til å holde det gående lenge, da dette er en
 536 butikk jeg kommer til å besøke ofte.  Butikken er et funn å ha i
 537 nabolaget for oss som liker å bygge litt selv. :)</p>
 538 </div>
 539       <div class="tags">
 540
 541
 542         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>.
 543
 544
 545       </div>
 546     </div>
 547     <div class="padding"></div>
 548
 549     <div class="entry">
 550       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Visualizing_GSM_radio_chatter_using_gr_gsm_and_Hopglass.html">Visualizing GSM radio chatter using gr-gsm and Hopglass</a></div>
 551       <div class="date">29th September 2017</div>
 552       <div class="body"><p>Every mobile phone announce its existence over radio to the nearby
 553 mobile cell towers.  And this radio chatter is available for anyone
 554 with a radio receiver capable of receiving them.  Details about the
 555 mobile phones with very good accuracy is of course collected by the
 556 phone companies, but this is not the topic of this blog post.  The
 557 mobile phone radio chatter make it possible to figure out when a cell
 558 phone is nearby, as it include the SIM card ID (IMSI).  By paying
 559 attention over time, one can see when a phone arrive and when it leave
 560 an area.  I believe it would be nice to make this information more
 561 available to the general public, to make more people aware of how
 562 their phones are announcing their whereabouts to anyone that care to
 563 listen.</p>
 564
 565 <p>I am very happy to report that we managed to get something
 566 visualizing this information up and running for
 567 <a href="http://norwaymakers.org/osf17">Oslo Skaperfestival 2017</a>
 568 (Oslo Makers Festival) taking place today and tomorrow at Deichmanske
 569 library.  The solution is based on the
 570 <a href="http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html">simple
 571 recipe for listening to GSM chatter</a> I posted a few days ago, and
 572 will show up at the stand of <a href="http://sonen.ifi.uio.no/">Åpen
 573 Sone from the Computer Science department of the University of
 574 Oslo</a>.  The presentation will show the nearby mobile phones (aka
 575 IMSIs) as dots in a web browser graph, with lines to the dot
 576 representing mobile base station it is talking to. It was working in
 577 the lab yesterday, and was moved into place this morning.</p>
 578
 579 <p>We set up a fairly powerful desktop machine using Debian
 580 Buster/Testing with several (five, I believe) RTL2838 DVB-T receivers
 581 connected and visualize the visible cell phone towers using an
 582 <a href="https://github.com/marlow925/hopglass">English version of
 583 Hopglass</a>.  A fairly powerfull machine is needed as the
 584 grgsm_livemon_headless processes from
 585 <a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a> converting
 586 the radio signal to data packages is quite CPU intensive.</p>
 587
 588 <p>The frequencies to listen to, are identified using a slightly
 589 patched scan-and-livemon (to set the --args values for each receiver),
 590 and the Hopglass data is generated using the
 591 <a href="https://github.com/petterreinholdtsen/IMSI-catcher/tree/meshviewer-output">patches
 592 in my meshviewer-output branch</a>.  For some reason we could not get
 593 more than four SDRs working.  There is also a geographical map trying
 594 to show the location of the base stations, but I believe their
 595 coordinates are hardcoded to some random location in Germany, I
 596 believe.  The code should be replaced with code to look up location in
 597 a text file, a sqlite database or one of the online databases
 598 mentioned in
 599 <a href="https://github.com/Oros42/IMSI-catcher/issues/14">the github
 600 issue for the topic</a>.
 601
 602 <p>If this sound interesting, visit the stand at the festival!</p>
 603 </div>
 604       <div class="tags">
 605
 606
 607         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/surveillance">surveillance</a>.
 608
 609
 610       </div>
 611     </div>
 612     <div class="padding"></div>
 613
 614     <div class="entry">
 615       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html">Easier recipe to observe the cell phones around you</a></div>
 616       <div class="date">24th September 2017</div>
 617       <div class="body"><p>A little more than a month ago I wrote
 618 <a href="http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html">how
 619 to observe the SIM card ID (aka IMSI number) of mobile phones talking
 620 to nearby mobile phone base stations using Debian GNU/Linux and a
 621 cheap USB software defined radio</a>, and thus being able to pinpoint
 622 the location of people and equipment (like cars and trains) with an
 623 accuracy of a few kilometer.  Since then we have worked to make the
 624 procedure even simpler, and it is now possible to do this without any
 625 manual frequency tuning and without building your own packages.</p>
 626
 627 <p>The <a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a>
 628 package is now included in Debian testing and unstable, and the
 629 IMSI-catcher code no longer require root access to fetch and decode
 630 the GSM data collected using gr-gsm.</p>
 631
 632 <p>Here is an updated recipe, using packages built by Debian and a git
 633 clone of two python scripts:</p>
 634
 635 <ol>
 636
 637 <li>Start with a Debian machine running the Buster version (aka
 638   testing).</li>
 639
 640 <li>Run '<tt>apt install gr-gsm python-numpy python-scipy
 641   python-scapy</tt>' as root to install required packages.</li>
 642
 643 <li>Fetch the code decoding GSM packages using '<tt>git clone
 644   github.com/Oros42/IMSI-catcher.git</tt>'.</li>
 645
 646 <li>Insert USB software defined radio supported by GNU Radio.</li>
 647
 648 <li>Enter the IMSI-catcher directory and run '<tt>python
 649   scan-and-livemon</tt>' to locate the frequency of nearby base
 650   stations and start listening for GSM packages on one of them.</li>
 651
 652 <li>Enter the IMSI-catcher directory and run '<tt>python
 653   simple_IMSI-catcher.py</tt>' to display the collected information.</li>
 654
 655 </ol>
 656
 657 <p>Note, due to a bug somewhere the scan-and-livemon program (actually
 658 <a href="https://github.com/ptrkrysik/gr-gsm/issues/336">its underlying
 659 program grgsm_scanner</a>) do not work with the HackRF radio.  It does
 660 work with RTL 8232 and other similar USB radio receivers you can get
 661 very cheaply
 662 (<a href="https://www.ebay.com/sch/items/?_nkw=rtl+2832">for example
 663 from ebay</a>), so for now the solution is to scan using the RTL radio
 664 and only use HackRF for fetching GSM data.</p>
 665
 666 <p>As far as I can tell, a cell phone only show up on one of the
 667 frequencies at the time, so if you are going to track and count every
 668 cell phone around you, you need to listen to all the frequencies used.
 669 To listen to several frequencies, use the --numrecv argument to
 670 scan-and-livemon to use several receivers.  Further, I am not sure if
 671 phones using 3G or 4G will show as talking GSM to base stations, so
 672 this approach might not see all phones around you.  I typically see
 673 0-400 IMSI numbers an hour when looking around where I live.</p>
 674
 675 <p>I've tried to run the scanner on a
 676 <a href="https://wiki.debian.org/RaspberryPi">Raspberry Pi 2 and 3
 677 running Debian Buster</a>, but the grgsm_livemon_headless process seem
 678 to be too CPU intensive to keep up.  When GNU Radio print 'O' to
 679 stdout, I am told there it is caused by a buffer overflow between the
 680 radio and GNU Radio, caused by the program being unable to read the
 681 GSM data fast enough.  If you see a stream of 'O's from the terminal
 682 where you started scan-and-livemon, you need a give the process more
 683 CPU power.  Perhaps someone are able to optimize the code to a point
 684 where it become possible to set up RPi3 based GSM sniffers?  I tried
 685 using Raspbian instead of Debian, but there seem to be something wrong
 686 with GNU Radio on raspbian, causing glibc to abort().</p>
 687 </div>
 688       <div class="tags">
 689
 690
 691         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/surveillance">surveillance</a>.
 692
 693
 694       </div>
 695     </div>
 696     <div class="padding"></div>
 697
 698     <div class="entry">
 699       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_kaster_skygger_over_H_yre_og_Arbeiderpartiet.html">Datalagringsdirektivet kaster skygger over Høyre og Arbeiderpartiet</a></div>
 700       <div class="date"> 7th September 2017</div>
 701       <div class="body"><p>For noen dager siden publiserte Jon Wessel-Aas en bloggpost om
 702 «<a href="http://www.uhuru.biz/?p=1821">Konklusjonen om datalagring som
 703 EU-kommisjonen ikke ville at vi skulle få se</a>».  Det er en
 704 interessant gjennomgang av EU-domstolens syn på snurpenotovervåkning
 705 av befolkningen, som er klar på at det er i strid med
 706 EU-lovgivingen.</p>
 707
 708 <p>Valgkampen går for fullt i Norge, og om noen få dager er siste
 709 frist for å avgi stemme.  En ting er sikkert, Høyre og Arbeiderpartiet
 710 får ikke min stemme
 711 <a href="http://people.skolelinux.org/pere/blog/Datalagringsdirektivet_gj_r_at_Oslo_H_yre_og_Arbeiderparti_ikke_f_r_min_stemme_i__r.html">denne
 712 gangen heller</a>.  Jeg har ikke glemt at de tvang igjennom loven som
 713 skulle pålegge alle data- og teletjenesteleverandører å overvåke alle
 714 sine kunder.  En lov som er vedtatt, og aldri opphevet igjen.</p>
 715
 716 <p>Det er tydelig fra diskusjonen rundt grenseløs digital overvåkning
 717 (eller "Digital Grenseforsvar" som det kalles i Orvellisk nytale) at
 718 hverken Høyre og Arbeiderpartiet har noen prinsipielle sperrer mot å
 719 overvåke hele befolkningen, og diskusjonen så langt tyder på at flere
 720 av de andre partiene heller ikke har det. Mange av
 721 <a href="https://data.holderdeord.no/votes/1301946411e">de som stemte
 722 for Datalagringsdirektivet i Stortinget</a> (64 fra Arbeiderpartiet,
 723 25 fra Høyre) er fortsatt aktive og argumenterer fortsatt for å radere
 724 vekk mer av innbyggernes privatsfære.</p>
 725
 726 <p>Når myndighetene demonstrerer sin mistillit til folket, tror jeg
 727 folket selv bør legge litt innsats i å verne sitt privatliv, ved å ta
 728 i bruk ende-til-ende-kryptert kommunikasjon med sine kjente og kjære,
 729 og begrense hvor mye privat informasjon som deles med uvedkommende.
 730 Det er jo ingenting som tyder på at myndighetene kommer til å være vår
 731 privatsfære.
 732 <a href="http://people.skolelinux.org/pere/blog/How_to_talk_with_your_loved_ones_in_private.html">Det
 733 er mange muligheter</a>.  Selv har jeg litt sans for
 734 <a href="https://ring.cx/">Ring</a>, som er basert på p2p-teknologi
 735 uten sentral kontroll, er fri programvare, og støtter meldinger, tale
 736 og video.  Systemet er tilgjengelig ut av boksen fra
 737 <a href="https://tracker.debian.org/pkg/ring">Debian</a> og
 738 <a href="https://launchpad.net/ubuntu/+source/ring">Ubuntu</a>, og det
 739 finnes pakker for Android, MacOSX og Windows.  Foreløpig er det få
 740 brukere med Ring, slik at jeg også bruker
 741 <a href="https://signal.org/">Signal</a> som nettleserutvidelse.</p>
 742 </div>
 743       <div class="tags">
 744
 745
 746         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/dld">dld</a>, <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>, <a href="http://people.skolelinux.org/pere/blog/tags/valg">valg</a>.
 747
 748
 749       </div>
 750     </div>
 751     <div class="padding"></div>
 752
 753     <div class="entry">
 754       <div class="title"><a href="http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html">Simpler recipe on how to make a simple $7 IMSI Catcher using Debian</a></div>
 755       <div class="date"> 9th August 2017</div>
 756       <div class="body"><p>On friday, I came across an interesting article in the Norwegian
 757 web based ICT news magazine digi.no on
 758 <a href="https://www.digi.no/artikler/sikkerhetsforsker-lagde-enkel-imsi-catcher-for-60-kroner-na-kan-mobiler-kartlegges-av-alle/398588">how
 759 to collect the IMSI numbers of nearby cell phones</a> using the cheap
 760 DVB-T software defined radios.  The article refered to instructions
 761 and <a href="https://www.youtube.com/watch?v=UjwgNd_as30">a recipe by
 762 Keld Norman on Youtube on how to make a simple $7 IMSI Catcher</a>, and I decided to test them out.</p>
 763
 764 <p>The instructions said to use Ubuntu, install pip using apt (to
 765 bypass apt), use pip to install pybombs (to bypass both apt and pip),
 766 and the ask pybombs to fetch and build everything you need from
 767 scratch.  I wanted to see if I could do the same on the most recent
 768 Debian packages, but this did not work because pybombs tried to build
 769 stuff that no longer build with the most recent openssl library or
 770 some other version skew problem.  While trying to get this recipe
 771 working, I learned that the apt->pip->pybombs route was a long detour,
 772 and the only piece of software dependency missing in Debian was the
 773 gr-gsm package.  I also found out that the lead upstream developer of
 774 gr-gsm (the name stand for GNU Radio GSM) project already had a set of
 775 Debian packages provided in an Ubuntu PPA repository.  All I needed to
 776 do was to dget the Debian source package and built it.</p>
 777
 778 <p>The IMSI collector is a python script listening for packages on the
 779 loopback network device and printing to the terminal some specific GSM
 780 packages with IMSI numbers in them.  The code is fairly short and easy
 781 to understand.  The reason this work is because gr-gsm include a tool
 782 to read GSM data from a software defined radio like a DVB-T USB stick
 783 and other software defined radios, decode them and inject them into a
 784 network device on your Linux machine (using the loopback device by
 785 default).  This proved to work just fine, and I've been testing the
 786 collector for a few days now.</p>
 787
 788 <p>The updated and simpler recipe is thus to</p>
 789
 790 <ol>
 791
 792 <li>start with a Debian machine running Stretch or newer,</li>
 793
 794 <li>build and install the gr-gsm package available from
 795 <a href="http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/">http://ppa.launchpad.net/ptrkrysik/gr-gsm/ubuntu/pool/main/g/gr-gsm/</a>,</li>
 796
 797 <li>clone the git repostory from <a href="https://github.com/Oros42/IMSI-catcher">https://github.com/Oros42/IMSI-catcher</a>,</li>
 798
 799 <li>run grgsm_livemon and adjust the frequency until the terminal
 800 where it was started is filled with a stream of text (meaning you
 801 found a GSM station).</li>
 802
 803 <li>go into the IMSI-catcher directory and run 'sudo python simple_IMSI-catcher.py' to extract the IMSI numbers.</li>
 804
 805 </ol>
 806
 807 <p>To make it even easier in the future to get this sniffer up and
 808 running, I decided to package
 809 <a href="https://github.com/ptrkrysik/gr-gsm/">the gr-gsm project</a>
 810 for Debian (<a href="https://bugs.debian.org/871055">WNPP
 811 #871055</a>), and the package was uploaded into the NEW queue today.
 812 Luckily the gnuradio maintainer has promised to help me, as I do not
 813 know much about gnuradio stuff yet.</p>
 814
 815 <p>I doubt this "IMSI cacher" is anywhere near as powerfull as
 816 commercial tools like
 817 <a href="https://www.thespyphone.com/portable-imsi-imei-catcher/">The
 818 Spy Phone Portable IMSI / IMEI Catcher</a> or the
 819 <a href="https://en.wikipedia.org/wiki/Stingray_phone_tracker">Harris
 820 Stingray</a>, but I hope the existance of cheap alternatives can make
 821 more people realise how their whereabouts when carrying a cell phone
 822 is easily tracked.  Seeing the data flow on the screen, realizing that
 823 I live close to a police station and knowing that the police is also
 824 wearing cell phones, I wonder how hard it would be for criminals to
 825 track the position of the police officers to discover when there are
 826 police near by, or for foreign military forces to track the location
 827 of the Norwegian military forces, or for anyone to track the location
 828 of government officials...</p>
 829
 830 <p>It is worth noting that the data reported by the IMSI-catcher
 831 script mentioned above is only a fraction of the data broadcasted on
 832 the GSM network.  It will only collect one frequency at the time,
 833 while a typical phone will be using several frequencies, and not all
 834 phones will be using the frequencies tracked by the grgsm_livemod
 835 program.  Also, there is a lot of radio chatter being ignored by the
 836 simple_IMSI-catcher script, which would be collected by extending the
 837 parser code.  I wonder if gr-gsm can be set up to listen to more than
 838 one frequency?</p>
 839 </div>
 840       <div class="tags">
 841
 842
 843         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/surveillance">surveillance</a>.
 844
 845
 846       </div>
 847     </div>
 848     <div class="padding"></div>
 849
 850     <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>
 851     <div id="sidebar">
 852
 853
 854
 855 <h2>Archive</h2>
 856 <ul>
 857
 858 <li>2017
 859 <ul>
 860
 861 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/01/">January (4)</a></li>
 862
 863 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/02/">February (3)</a></li>
 864
 865 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/03/">March (5)</a></li>
 866
 867 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/04/">April (2)</a></li>
 868
 869 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/06/">June (5)</a></li>
 870
 871 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/07/">July (1)</a></li>
 872
 873 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/08/">August (1)</a></li>
 874
 875 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/09/">September (3)</a></li>
 876
 877 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/10/">October (5)</a></li>
 878
 879 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/11/">November (1)</a></li>
 880
 881 </ul></li>
 882
 883 <li>2016
 884 <ul>
 885
 886 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/01/">January (3)</a></li>
 887
 888 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/02/">February (2)</a></li>
 889
 890 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/03/">March (3)</a></li>
 891
 892 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/04/">April (8)</a></li>
 893
 894 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/05/">May (8)</a></li>
 895
 896 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/06/">June (2)</a></li>
 897
 898 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/07/">July (2)</a></li>
 899
 900 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/08/">August (5)</a></li>
 901
 902 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/09/">September (2)</a></li>
 903
 904 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/10/">October (3)</a></li>
 905
 906 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/11/">November (8)</a></li>
 907
 908 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/12/">December (5)</a></li>
 909
 910 </ul></li>
 911
 912 <li>2015
 913 <ul>
 914
 915 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
 916
 917 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
 918
 919 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
 920
 921 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
 922
 923 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/05/">May (3)</a></li>
 924
 925 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/06/">June (4)</a></li>
 926
 927 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/07/">July (6)</a></li>
 928
 929 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/08/">August (2)</a></li>
 930
 931 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/09/">September (2)</a></li>
 932
 933 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/10/">October (9)</a></li>
 934
 935 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/11/">November (6)</a></li>
 936
 937 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/12/">December (3)</a></li>
 938
 939 </ul></li>
 940
 941 <li>2014
 942 <ul>
 943
 944 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
 945
 946 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
 947
 948 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
 949
 950 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
 951
 952 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
 953
 954 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
 955
 956 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
 957
 958 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
 959
 960 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
 961
 962 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
 963
 964 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
 965
 966 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
 967
 968 </ul></li>
 969
 970 <li>2013
 971 <ul>
 972
 973 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 974
 975 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 976
 977 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 978
 979 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 980
 981 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 982
 983 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 984
 985 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 986
 987 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 988
 989 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 990
 991 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 992
 993 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
 994
 995 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
 996
 997 </ul></li>
 998
 999 <li>2012
1000 <ul>
1001
1002 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
1003
1004 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
1005
1006 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
1007
1008 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
1009
1010 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
1011
1012 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
1013
1014 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
1015
1016 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
1017
1018 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
1019
1020 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
1021
1022 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
1023
1024 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
1025
1026 </ul></li>
1027
1028 <li>2011
1029 <ul>
1030
1031 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
1032
1033 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
1034
1035 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
1036
1037 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
1038
1039 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
1040
1041 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
1042
1043 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
1044
1045 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
1046
1047 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
1048
1049 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
1050
1051 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
1052
1053 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
1054
1055 </ul></li>
1056
1057 <li>2010
1058 <ul>
1059
1060 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
1061
1062 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
1063
1064 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
1065
1066 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
1067
1068 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
1069
1070 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
1071
1072 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
1073
1074 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
1075
1076 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
1077
1078 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
1079
1080 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
1081
1082 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
1083
1084 </ul></li>
1085
1086 <li>2009
1087 <ul>
1088
1089 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
1090
1091 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
1092
1093 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
1094
1095 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
1096
1097 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
1098
1099 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
1100
1101 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
1102
1103 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
1104
1105 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
1106
1107 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
1108
1109 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
1110
1111 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
1112
1113 </ul></li>
1114
1115 <li>2008
1116 <ul>
1117
1118 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
1119
1120 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
1121
1122 </ul></li>
1123
1124 </ul>
1125
1126
1127
1128 <h2>Tags</h2>
1129 <ul>
1130
1131  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (14)</a></li>
1132
1133  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
1134
1135  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
1136
1137  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
1138
1139  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (9)</a></li>
1140
1141  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (16)</a></li>
1142
1143  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
1144
1145  <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
1146
1147  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (154)</a></li>
1148
1149  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (158)</a></li>
1150
1151  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook (4)</a></li>
1152
1153  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
1154
1155  <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (17)</a></li>
1156
1157  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (24)</a></li>
1158
1159  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
1160
1161  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (358)</a></li>
1162
1163  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
1164
1165  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
1166
1167  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (30)</a></li>
1168
1169  <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
1170
1171  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (18)</a></li>
1172
1173  <li><a href="http://people.skolelinux.org/pere/blog/tags/h264">h264 (20)</a></li>
1174
1175  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (42)</a></li>
1176
1177  <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (15)</a></li>
1178
1179  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (20)</a></li>
1180
1181  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
1182
1183  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
1184
1185  <li><a href="http://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
1186
1187  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
1188
1189  <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
1190
1191  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (39)</a></li>
1192
1193  <li><a href="http://people.skolelinux.org/pere/blog/tags/nice free software">nice free software (9)</a></li>
1194
1195  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (293)</a></li>
1196
1197  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (189)</a></li>
1198
1199  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (33)</a></li>
1200
1201  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
1202
1203  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (65)</a></li>
1204
1205  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (104)</a></li>
1206
1207  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (2)</a></li>
1208
1209  <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
1210
1211  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
1212
1213  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
1214
1215  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (10)</a></li>
1216
1217  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
1218
1219  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (5)</a></li>
1220
1221  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
1222
1223  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (53)</a></li>
1224
1225  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
1226
1227  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (5)</a></li>
1228
1229  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (55)</a></li>
1230
1231  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (6)</a></li>
1232
1233  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (12)</a></li>
1234
1235  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (52)</a></li>
1236
1237  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (4)</a></li>
1238
1239  <li><a href="http://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
1240
1241  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (9)</a></li>
1242
1243  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (59)</a></li>
1244
1245  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
1246
1247  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (40)</a></li>
1248
1249 </ul>
1250
1251
1252     </div>
1253     <p style="text-align: right">
1254  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
1255 </p>
1256
1257   </body>
1258 </html>