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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 cAnalysis of Data Corruption in the Storage Stack</a> -
  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> -
  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.</p>
  88
  89 <p>Just remember, in the end, it do not matter how redundant, or how
  90 fault tolerant your storage is, if you do not continuously monitor its
  91 status to detect and replace failed disks.</p>
  92 </div>
  93       <div class="tags">
  94
  95
  96         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>.
  97
  98
  99       </div>
 100     </div>
 101     <div class="padding"></div>
 102
 103     <div class="entry">
 104       <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>
 105       <div class="date">31st October 2017</div>
 106       <div class="body"><p>I was surprised today to learn that a friend in academia did not
 107 know there are easily available web services available for writing
 108 LaTeX documents as a team.  I thought it was common knowledge, but to
 109 make sure at least my readers are aware of it, I would like to mention
 110 these useful services for writing LaTeX documents.  Some of them even
 111 provide a WYSIWYG editor to ease writing even further.</p>
 112
 113 <p>There are two commercial services available,
 114 <a href="https://sharelatex.com">ShareLaTeX</a> and
 115 <a href="https://overleaf.com">Overleaf</a>.  They are very easy to
 116 use.  Just start a new document, select which publisher to write for
 117 (ie which LaTeX style to use), and start writing.  Note, these two
 118 have announced their intention to join forces, so soon it will only be
 119 one joint service.  I've used both for different documents, and they
 120 work just fine.  While
 121 <a href="https://github.com/sharelatex/sharelatex">ShareLaTeX is free
 122 software</a>, while the latter is not.  According to <a
 123 href="https://www.overleaf.com/help/17-is-overleaf-open-source">a
 124 announcement from Overleaf</a>, they plan to keep the ShareLaTeX code
 125 base maintained as free software.</p>
 126
 127 But these two are not the only alternatives.
 128 <a href="https://app.fiduswriter.org/">Fidus Writer</a> is another free
 129 software solution with <a href="https://github.com/fiduswriter">the
 130 source available on github</a>.  I have not used it myself.  Several
 131 others can be found on the nice
 132 <a href="https://alternativeto.net/software/sharelatex/">alterntiveTo
 133 web service</a>.
 134
 135 <p>If you like Google Docs or Etherpad, but would like to write
 136 documents in LaTeX, you should check out these services.  You can even
 137 host your own, if you want to. :)</p>
 138
 139 </div>
 140       <div class="tags">
 141
 142
 143         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 144
 145
 146       </div>
 147     </div>
 148     <div class="padding"></div>
 149
 150     <div class="entry">
 151       <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>
 152       <div class="date">25th October 2017</div>
 153       <div class="body"><p>Recently, I needed to automatically check the copyright status of a
 154 set of <a href="http://www.imdb.com/">The Internet Movie database
 155 (IMDB)</a> entries, to figure out which one of the movies they refer
 156 to can be freely distributed on the Internet.  This proved to be
 157 harder than it sounds.  IMDB for sure list movies without any
 158 copyright protection, where the copyright protection has expired or
 159 where the movie is lisenced using a permissive license like one from
 160 Creative Commons.  These are mixed with copyright protected movies,
 161 and there seem to be no way to separate these classes of movies using
 162 the information in IMDB.</p>
 163
 164 <p>First I tried to look up entries manually in IMDB,
 165 <a href="https://www.wikipedia.org/">Wikipedia</a> and
 166 <a href="https://www.archive.org/">The Internet Archive</a>, to get a
 167 feel how to do this.  It is hard to know for sure using these sources,
 168 but it should be possible to be reasonable confident a movie is "out
 169 of copyright" with a few hours work per movie.  As I needed to check
 170 almost 20,000 entries, this approach was not sustainable.  I simply
 171 can not work around the clock for about 6 years to check this data
 172 set.</p>
 173
 174 <p>I asked the people behind The Internet Archive if they could
 175 introduce a new metadata field in their metadata XML for IMDB ID, but
 176 was told that they leave it completely to the uploaders to update the
 177 metadata.  Some of the metadata entries had IMDB links in the
 178 description, but I found no way to download all metadata files in bulk
 179 to locate those ones and put that approach aside.</p>
 180
 181 <p>In the process I noticed several Wikipedia articles about movies
 182 had links to both IMDB and The Internet Archive, and it occured to me
 183 that I could use the Wikipedia RDF data set to locate entries with
 184 both, to at least get a lower bound on the number of movies on The
 185 Internet Archive with a IMDB ID.  This is useful based on the
 186 assumption that movies distributed by The Internet Archive can be
 187 legally distributed on the Internet.  With some help from the RDF
 188 community (thank you DanC), I was able to come up with this query to
 189 pass to <a href="https://query.wikidata.org/">the SPARQL interface on
 190 Wikidata</a>:
 191
 192 <p><pre>
 193 SELECT ?work ?imdb ?ia ?when ?label
 194 WHERE
 195 {
 196   ?work wdt:P31/wdt:P279* wd:Q11424.
 197   ?work wdt:P345 ?imdb.
 198   ?work wdt:P724 ?ia.
 199   OPTIONAL {
 200         ?work wdt:P577 ?when.
 201         ?work rdfs:label ?label.
 202         FILTER(LANG(?label) = "en").
 203   }
 204 }
 205 </pre></p>
 206
 207 <p>If I understand the query right, for every film entry anywhere in
 208 Wikpedia, it will return the IMDB ID and The Internet Archive ID, and
 209 when the movie was released and its English title, if either or both
 210 of the latter two are available.  At the moment the result set contain
 211 2338 entries.  Of course, it depend on volunteers including both
 212 correct IMDB and The Internet Archive IDs in the wikipedia articles
 213 for the movie.  It should be noted that the result will include
 214 duplicates if the movie have entries in several languages.  There are
 215 some bogus entries, either because The Internet Archive ID contain a
 216 typo or because the movie is not available from The Internet Archive.
 217 I did not verify the IMDB IDs, as I am unsure how to do that
 218 automatically.</p>
 219
 220 <p>I wrote a small python script to extract the data set from Wikidata
 221 and check if the XML metadata for the movie is available from The
 222 Internet Archive, and after around 1.5 hour it produced a list of 2097
 223 free movies and their IMDB ID.  In total, 171 entries in Wikidata lack
 224 the refered Internet Archive entry.  I assume the 70 "disappearing"
 225 entries (ie 2338-2097-171) are duplicate entries.</p>
 226
 227 <p>This is not too bad, given that The Internet Archive report to
 228 contain <a href="https://archive.org/details/feature_films">5331
 229 feature films</a> at the moment, but it also mean more than 3000
 230 movies are missing on Wikipedia or are missing the pair of references
 231 on Wikipedia.</p>
 232
 233 <p>I was curious about the distribution by release year, and made a
 234 little graph to show how the amount of free movies is spread over the
 235 years:<p>
 236
 237 <p><img src="http://people.skolelinux.org/pere/blog/images/2017-10-25-verk-i-det-fri-filmer.png"></p>
 238
 239 <p>I expect the relative distribution of the remaining 3000 movies to
 240 be similar.</p>
 241
 242 <p>If you want to help, and want to ensure Wikipedia can be used to
 243 cross reference The Internet Archive and The Internet Movie Database,
 244 please make sure entries like this are listed under the "External
 245 links" heading on the Wikipedia article for the movie:</p>
 246
 247 <p><pre>
 248 * {{Internet Archive film|id=FightingLady}}
 249 * {{IMDb title|id=0036823|title=The Fighting Lady}}
 250 </pre></p>
 251
 252 <p>Please verify the links on the final page, to make sure you did not
 253 introduce a typo.</p>
 254
 255 <p>Here is the complete list, if you want to correct the 171
 256 identified Wikipedia entries with broken links to The Internet
 257 Archive: <a href="http://www.wikidata.org/entity/Q1140317">Q1140317</a>,
 258 <a href="http://www.wikidata.org/entity/Q458656">Q458656</a>,
 259 <a href="http://www.wikidata.org/entity/Q458656">Q458656</a>,
 260 <a href="http://www.wikidata.org/entity/Q470560">Q470560</a>,
 261 <a href="http://www.wikidata.org/entity/Q743340">Q743340</a>,
 262 <a href="http://www.wikidata.org/entity/Q822580">Q822580</a>,
 263 <a href="http://www.wikidata.org/entity/Q480696">Q480696</a>,
 264 <a href="http://www.wikidata.org/entity/Q128761">Q128761</a>,
 265 <a href="http://www.wikidata.org/entity/Q1307059">Q1307059</a>,
 266 <a href="http://www.wikidata.org/entity/Q1335091">Q1335091</a>,
 267 <a href="http://www.wikidata.org/entity/Q1537166">Q1537166</a>,
 268 <a href="http://www.wikidata.org/entity/Q1438334">Q1438334</a>,
 269 <a href="http://www.wikidata.org/entity/Q1479751">Q1479751</a>,
 270 <a href="http://www.wikidata.org/entity/Q1497200">Q1497200</a>,
 271 <a href="http://www.wikidata.org/entity/Q1498122">Q1498122</a>,
 272 <a href="http://www.wikidata.org/entity/Q865973">Q865973</a>,
 273 <a href="http://www.wikidata.org/entity/Q834269">Q834269</a>,
 274 <a href="http://www.wikidata.org/entity/Q841781">Q841781</a>,
 275 <a href="http://www.wikidata.org/entity/Q841781">Q841781</a>,
 276 <a href="http://www.wikidata.org/entity/Q1548193">Q1548193</a>,
 277 <a href="http://www.wikidata.org/entity/Q499031">Q499031</a>,
 278 <a href="http://www.wikidata.org/entity/Q1564769">Q1564769</a>,
 279 <a href="http://www.wikidata.org/entity/Q1585239">Q1585239</a>,
 280 <a href="http://www.wikidata.org/entity/Q1585569">Q1585569</a>,
 281 <a href="http://www.wikidata.org/entity/Q1624236">Q1624236</a>,
 282 <a href="http://www.wikidata.org/entity/Q4796595">Q4796595</a>,
 283 <a href="http://www.wikidata.org/entity/Q4853469">Q4853469</a>,
 284 <a href="http://www.wikidata.org/entity/Q4873046">Q4873046</a>,
 285 <a href="http://www.wikidata.org/entity/Q915016">Q915016</a>,
 286 <a href="http://www.wikidata.org/entity/Q4660396">Q4660396</a>,
 287 <a href="http://www.wikidata.org/entity/Q4677708">Q4677708</a>,
 288 <a href="http://www.wikidata.org/entity/Q4738449">Q4738449</a>,
 289 <a href="http://www.wikidata.org/entity/Q4756096">Q4756096</a>,
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 292 <a href="http://www.wikidata.org/entity/Q882066">Q882066</a>,
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 295 <a href="http://www.wikidata.org/entity/Q204191">Q204191</a>,
 296 <a href="http://www.wikidata.org/entity/Q1194170">Q1194170</a>,
 297 <a href="http://www.wikidata.org/entity/Q940014">Q940014</a>,
 298 <a href="http://www.wikidata.org/entity/Q946863">Q946863</a>,
 299 <a href="http://www.wikidata.org/entity/Q172837">Q172837</a>,
 300 <a href="http://www.wikidata.org/entity/Q573077">Q573077</a>,
 301 <a href="http://www.wikidata.org/entity/Q1219005">Q1219005</a>,
 302 <a href="http://www.wikidata.org/entity/Q1219599">Q1219599</a>,
 303 <a href="http://www.wikidata.org/entity/Q1643798">Q1643798</a>,
 304 <a href="http://www.wikidata.org/entity/Q1656352">Q1656352</a>,
 305 <a href="http://www.wikidata.org/entity/Q1659549">Q1659549</a>,
 306 <a href="http://www.wikidata.org/entity/Q1660007">Q1660007</a>,
 307 <a href="http://www.wikidata.org/entity/Q1698154">Q1698154</a>,
 308 <a href="http://www.wikidata.org/entity/Q1737980">Q1737980</a>,
 309 <a href="http://www.wikidata.org/entity/Q1877284">Q1877284</a>,
 310 <a href="http://www.wikidata.org/entity/Q1199354">Q1199354</a>,
 311 <a href="http://www.wikidata.org/entity/Q1199354">Q1199354</a>,
 312 <a href="http://www.wikidata.org/entity/Q1199451">Q1199451</a>,
 313 <a href="http://www.wikidata.org/entity/Q1211871">Q1211871</a>,
 314 <a href="http://www.wikidata.org/entity/Q1212179">Q1212179</a>,
 315 <a href="http://www.wikidata.org/entity/Q1238382">Q1238382</a>,
 316 <a href="http://www.wikidata.org/entity/Q4906454">Q4906454</a>,
 317 <a href="http://www.wikidata.org/entity/Q320219">Q320219</a>,
 318 <a href="http://www.wikidata.org/entity/Q1148649">Q1148649</a>,
 319 <a href="http://www.wikidata.org/entity/Q645094">Q645094</a>,
 320 <a href="http://www.wikidata.org/entity/Q5050350">Q5050350</a>,
 321 <a href="http://www.wikidata.org/entity/Q5166548">Q5166548</a>,
 322 <a href="http://www.wikidata.org/entity/Q2677926">Q2677926</a>,
 323 <a href="http://www.wikidata.org/entity/Q2698139">Q2698139</a>,
 324 <a href="http://www.wikidata.org/entity/Q2707305">Q2707305</a>,
 325 <a href="http://www.wikidata.org/entity/Q2740725">Q2740725</a>,
 326 <a href="http://www.wikidata.org/entity/Q2024780">Q2024780</a>,
 327 <a href="http://www.wikidata.org/entity/Q2117418">Q2117418</a>,
 328 <a href="http://www.wikidata.org/entity/Q2138984">Q2138984</a>,
 329 <a href="http://www.wikidata.org/entity/Q1127992">Q1127992</a>,
 330 <a href="http://www.wikidata.org/entity/Q1058087">Q1058087</a>,
 331 <a href="http://www.wikidata.org/entity/Q1070484">Q1070484</a>,
 332 <a href="http://www.wikidata.org/entity/Q1080080">Q1080080</a>,
 333 <a href="http://www.wikidata.org/entity/Q1090813">Q1090813</a>,
 334 <a href="http://www.wikidata.org/entity/Q1251918">Q1251918</a>,
 335 <a href="http://www.wikidata.org/entity/Q1254110">Q1254110</a>,
 336 <a href="http://www.wikidata.org/entity/Q1257070">Q1257070</a>,
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 338 <a href="http://www.wikidata.org/entity/Q1197410">Q1197410</a>,
 339 <a href="http://www.wikidata.org/entity/Q1198423">Q1198423</a>,
 340 <a href="http://www.wikidata.org/entity/Q706951">Q706951</a>,
 341 <a href="http://www.wikidata.org/entity/Q723239">Q723239</a>,
 342 <a href="http://www.wikidata.org/entity/Q2079261">Q2079261</a>,
 343 <a href="http://www.wikidata.org/entity/Q1171364">Q1171364</a>,
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 345 <a href="http://www.wikidata.org/entity/Q5166611">Q5166611</a>,
 346 <a href="http://www.wikidata.org/entity/Q5166611">Q5166611</a>,
 347 <a href="http://www.wikidata.org/entity/Q324513">Q324513</a>,
 348 <a href="http://www.wikidata.org/entity/Q374172">Q374172</a>,
 349 <a href="http://www.wikidata.org/entity/Q7533269">Q7533269</a>,
 350 <a href="http://www.wikidata.org/entity/Q970386">Q970386</a>,
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 426 <a href="http://www.wikidata.org/entity/Q3429733">Q3429733</a>,
 427 <a href="http://www.wikidata.org/entity/Q774474">Q774474</a></p>
 428 </div>
 429       <div class="tags">
 430
 431
 432         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>.
 433
 434
 435       </div>
 436     </div>
 437     <div class="padding"></div>
 438
 439     <div class="entry">
 440       <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>
 441       <div class="date">14th October 2017</div>
 442       <div class="body"><p>I find it fascinating how many of the people being locked inside
 443 the proposed border wall between USA and Mexico support the idea.  The
 444 proposal to keep Mexicans out reminds me of
 445 <a href="http://www.history.com/news/10-things-you-may-not-know-about-the-berlin-wall">the
 446 propaganda twist from the East Germany government</a> calling the wall
 447 the “Antifascist Bulwark” after erecting the Berlin Wall, claiming
 448 that the wall was erected to keep enemies from creeping into East
 449 Germany, while it was obvious to the people locked inside it that it
 450 was erected to keep the people from escaping.</p>
 451
 452 <p>Do the people in USA supporting this wall really believe it is a
 453 one way wall, only keeping people on the outside from getting in,
 454 while not keeping people in the inside from getting out?</p>
 455 </div>
 456       <div class="tags">
 457
 458
 459         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 460
 461
 462       </div>
 463     </div>
 464     <div class="padding"></div>
 465
 466     <div class="entry">
 467       <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>
 468       <div class="date"> 9th October 2017</div>
 469       <div class="body"><p>At my nearby maker space,
 470 <a href="http://sonen.ifi.uio.no/">Sonen</a>, I heard the story that it
 471 was easier to generate gcode files for theyr 3D printers (Ultimake 2+)
 472 on Windows and MacOS X than Linux, because the software involved had
 473 to be manually compiled and set up on Linux while premade packages
 474 worked out of the box on Windows and MacOS X.  I found this annoying,
 475 as the software involved,
 476 <a href="https://github.com/Ultimaker/Cura">Cura</a>, is free software
 477 and should be trivial to get up and running on Linux if someone took
 478 the time to package it for the relevant distributions.  I even found
 479 <a href="https://bugs.debian.org/706656">a request for adding into
 480 Debian</a> from 2013, which had seem some activity over the years but
 481 never resulted in the software showing up in Debian.  So a few days
 482 ago I offered my help to try to improve the situation.</p>
 483
 484 <p>Now I am very happy to see that all the packages required by a
 485 working Cura in Debian are uploaded into Debian and waiting in the NEW
 486 queue for the ftpmasters to have a look.  You can track the progress
 487 on
 488 <a href="https://qa.debian.org/developer.php?email=3dprinter-general%40lists.alioth.debian.org">the
 489 status page for the 3D printer team</a>.</p>
 490
 491 <p>The uploaded packages are a bit behind upstream, and was uploaded
 492 now to get slots in <a href="https://ftp-master.debian.org/new.html">the NEW
 493 queue</a> while we work up updating the packages to the latest
 494 upstream version.</p>
 495
 496 <p>On a related note, two competitors for Cura, which I found harder
 497 to use and was unable to configure correctly for Ultimaker 2+ in the
 498 short time I spent on it, are already in Debian.  If you are looking
 499 for 3D printer "slicers" and want something already available in
 500 Debian, check out
 501 <a href="https://tracker.debian.org/pkg/slic3r">slic3r</a> and
 502 <a href="https://tracker.debian.org/pkg/slic3r-prusa">slic3r-prusa</a>.
 503 The latter is a fork of the former.</p>
 504 </div>
 505       <div class="tags">
 506
 507
 508         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>.
 509
 510
 511       </div>
 512     </div>
 513     <div class="padding"></div>
 514
 515     <div class="entry">
 516       <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>
 517       <div class="date"> 4th October 2017</div>
 518       <div class="body">Når jeg holder på med ulike prosjekter, så trenger jeg stadig ulike
 519 skruer.  Det siste prosjektet jeg holder på med er å lage
 520 <a href="https://www.thingiverse.com/thing:676916">en boks til en
 521 HDMI-touch-skjerm</a> som skal brukes med Raspberry Pi.  Boksen settes
 522 sammen med skruer og bolter, og jeg har vært i tvil om hvor jeg kan
 523 få tak i de riktige skruene.  Clas Ohlson og Jernia i nærheten har
 524 sjelden hatt det jeg trenger.  Men her om dagen fikk jeg et fantastisk
 525 tips for oss som bor i Oslo.
 526 <a href="http://www.zachskruer.no/">Zachariassen Jernvare AS</a> i
 527 <a href="http://www.openstreetmap.org/?mlat=59.93421&mlon=10.76795#map=19/59.93421/10.76795">Hegermannsgate
 528 23A på Torshov</a> har et fantastisk utvalg, og åpent mellom 09:00 og
 529 17:00.  De selger skruer, muttere, bolter, skiver etc i løs vekt, og
 530 så langt har jeg fått alt jeg har lett etter.  De har i tillegg det
 531 meste av annen jernvare, som verktøy, lamper, ledninger, etc.  Jeg
 532 håper de har nok kunder til å holde det gående lenge, da dette er en
 533 butikk jeg kommer til å besøke ofte.  Butikken er et funn å ha i
 534 nabolaget for oss som liker å bygge litt selv. :)</p>
 535 </div>
 536       <div class="tags">
 537
 538
 539         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk</a>.
 540
 541
 542       </div>
 543     </div>
 544     <div class="padding"></div>
 545
 546     <div class="entry">
 547       <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>
 548       <div class="date">29th September 2017</div>
 549       <div class="body"><p>Every mobile phone announce its existence over radio to the nearby
 550 mobile cell towers.  And this radio chatter is available for anyone
 551 with a radio receiver capable of receiving them.  Details about the
 552 mobile phones with very good accuracy is of course collected by the
 553 phone companies, but this is not the topic of this blog post.  The
 554 mobile phone radio chatter make it possible to figure out when a cell
 555 phone is nearby, as it include the SIM card ID (IMSI).  By paying
 556 attention over time, one can see when a phone arrive and when it leave
 557 an area.  I believe it would be nice to make this information more
 558 available to the general public, to make more people aware of how
 559 their phones are announcing their whereabouts to anyone that care to
 560 listen.</p>
 561
 562 <p>I am very happy to report that we managed to get something
 563 visualizing this information up and running for
 564 <a href="http://norwaymakers.org/osf17">Oslo Skaperfestival 2017</a>
 565 (Oslo Makers Festival) taking place today and tomorrow at Deichmanske
 566 library.  The solution is based on the
 567 <a href="http://people.skolelinux.org/pere/blog/Easier_recipe_to_observe_the_cell_phones_around_you.html">simple
 568 recipe for listening to GSM chatter</a> I posted a few days ago, and
 569 will show up at the stand of <a href="http://sonen.ifi.uio.no/">Åpen
 570 Sone from the Computer Science department of the University of
 571 Oslo</a>.  The presentation will show the nearby mobile phones (aka
 572 IMSIs) as dots in a web browser graph, with lines to the dot
 573 representing mobile base station it is talking to. It was working in
 574 the lab yesterday, and was moved into place this morning.</p>
 575
 576 <p>We set up a fairly powerful desktop machine using Debian
 577 Buster/Testing with several (five, I believe) RTL2838 DVB-T receivers
 578 connected and visualize the visible cell phone towers using an
 579 <a href="https://github.com/marlow925/hopglass">English version of
 580 Hopglass</a>.  A fairly powerfull machine is needed as the
 581 grgsm_livemon_headless processes from
 582 <a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a> converting
 583 the radio signal to data packages is quite CPU intensive.</p>
 584
 585 <p>The frequencies to listen to, are identified using a slightly
 586 patched scan-and-livemon (to set the --args values for each receiver),
 587 and the Hopglass data is generated using the
 588 <a href="https://github.com/petterreinholdtsen/IMSI-catcher/tree/meshviewer-output">patches
 589 in my meshviewer-output branch</a>.  For some reason we could not get
 590 more than four SDRs working.  There is also a geographical map trying
 591 to show the location of the base stations, but I believe their
 592 coordinates are hardcoded to some random location in Germany, I
 593 believe.  The code should be replaced with code to look up location in
 594 a text file, a sqlite database or one of the online databases
 595 mentioned in
 596 <a href="https://github.com/Oros42/IMSI-catcher/issues/14">the github
 597 issue for the topic</a>.
 598
 599 <p>If this sound interesting, visit the stand at the festival!</p>
 600 </div>
 601       <div class="tags">
 602
 603
 604         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>.
 605
 606
 607       </div>
 608     </div>
 609     <div class="padding"></div>
 610
 611     <div class="entry">
 612       <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>
 613       <div class="date">24th September 2017</div>
 614       <div class="body"><p>A little more than a month ago I wrote
 615 <a href="http://people.skolelinux.org/pere/blog/Simpler_recipe_on_how_to_make_a_simple__7_IMSI_Catcher_using_Debian.html">how
 616 to observe the SIM card ID (aka IMSI number) of mobile phones talking
 617 to nearby mobile phone base stations using Debian GNU/Linux and a
 618 cheap USB software defined radio</a>, and thus being able to pinpoint
 619 the location of people and equipment (like cars and trains) with an
 620 accuracy of a few kilometer.  Since then we have worked to make the
 621 procedure even simpler, and it is now possible to do this without any
 622 manual frequency tuning and without building your own packages.</p>
 623
 624 <p>The <a href="https://tracker.debian.org/pkg/gr-gsm">gr-gsm</a>
 625 package is now included in Debian testing and unstable, and the
 626 IMSI-catcher code no longer require root access to fetch and decode
 627 the GSM data collected using gr-gsm.</p>
 628
 629 <p>Here is an updated recipe, using packages built by Debian and a git
 630 clone of two python scripts:</p>
 631
 632 <ol>
 633
 634 <li>Start with a Debian machine running the Buster version (aka
 635   testing).</li>
 636
 637 <li>Run '<tt>apt install gr-gsm python-numpy python-scipy
 638   python-scapy</tt>' as root to install required packages.</li>
 639
 640 <li>Fetch the code decoding GSM packages using '<tt>git clone
 641   github.com/Oros42/IMSI-catcher.git</tt>'.</li>
 642
 643 <li>Insert USB software defined radio supported by GNU Radio.</li>
 644
 645 <li>Enter the IMSI-catcher directory and run '<tt>python
 646   scan-and-livemon</tt>' to locate the frequency of nearby base
 647   stations and start listening for GSM packages on one of them.</li>
 648
 649 <li>Enter the IMSI-catcher directory and run '<tt>python
 650   simple_IMSI-catcher.py</tt>' to display the collected information.</li>
 651
 652 </ol>
 653
 654 <p>Note, due to a bug somewhere the scan-and-livemon program (actually
 655 <a href="https://github.com/ptrkrysik/gr-gsm/issues/336">its underlying
 656 program grgsm_scanner</a>) do not work with the HackRF radio.  It does
 657 work with RTL 8232 and other similar USB radio receivers you can get
 658 very cheaply
 659 (<a href="https://www.ebay.com/sch/items/?_nkw=rtl+2832">for example
 660 from ebay</a>), so for now the solution is to scan using the RTL radio
 661 and only use HackRF for fetching GSM data.</p>
 662
 663 <p>As far as I can tell, a cell phone only show up on one of the
 664 frequencies at the time, so if you are going to track and count every
 665 cell phone around you, you need to listen to all the frequencies used.
 666 To listen to several frequencies, use the --numrecv argument to
 667 scan-and-livemon to use several receivers.  Further, I am not sure if
 668 phones using 3G or 4G will show as talking GSM to base stations, so
 669 this approach might not see all phones around you.  I typically see
 670 0-400 IMSI numbers an hour when looking around where I live.</p>
 671
 672 <p>I've tried to run the scanner on a
 673 <a href="https://wiki.debian.org/RaspberryPi">Raspberry Pi 2 and 3
 674 running Debian Buster</a>, but the grgsm_livemon_headless process seem
 675 to be too CPU intensive to keep up.  When GNU Radio print 'O' to
 676 stdout, I am told there it is caused by a buffer overflow between the
 677 radio and GNU Radio, caused by the program being unable to read the
 678 GSM data fast enough.  If you see a stream of 'O's from the terminal
 679 where you started scan-and-livemon, you need a give the process more
 680 CPU power.  Perhaps someone are able to optimize the code to a point
 681 where it become possible to set up RPi3 based GSM sniffers?  I tried
 682 using Raspbian instead of Debian, but there seem to be something wrong
 683 with GNU Radio on raspbian, causing glibc to abort().</p>
 684 </div>
 685       <div class="tags">
 686
 687
 688         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>.
 689
 690
 691       </div>
 692     </div>
 693     <div class="padding"></div>
 694
 695     <div class="entry">
 696       <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>
 697       <div class="date"> 7th September 2017</div>
 698       <div class="body"><p>For noen dager siden publiserte Jon Wessel-Aas en bloggpost om
 699 «<a href="http://www.uhuru.biz/?p=1821">Konklusjonen om datalagring som
 700 EU-kommisjonen ikke ville at vi skulle få se</a>».  Det er en
 701 interessant gjennomgang av EU-domstolens syn på snurpenotovervåkning
 702 av befolkningen, som er klar på at det er i strid med
 703 EU-lovgivingen.</p>
 704
 705 <p>Valgkampen går for fullt i Norge, og om noen få dager er siste
 706 frist for å avgi stemme.  En ting er sikkert, Høyre og Arbeiderpartiet
 707 får ikke min stemme
 708 <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
 709 gangen heller</a>.  Jeg har ikke glemt at de tvang igjennom loven som
 710 skulle pålegge alle data- og teletjenesteleverandører å overvåke alle
 711 sine kunder.  En lov som er vedtatt, og aldri opphevet igjen.</p>
 712
 713 <p>Det er tydelig fra diskusjonen rundt grenseløs digital overvåkning
 714 (eller "Digital Grenseforsvar" som det kalles i Orvellisk nytale) at
 715 hverken Høyre og Arbeiderpartiet har noen prinsipielle sperrer mot å
 716 overvåke hele befolkningen, og diskusjonen så langt tyder på at flere
 717 av de andre partiene heller ikke har det. Mange av
 718 <a href="https://data.holderdeord.no/votes/1301946411e">de som stemte
 719 for Datalagringsdirektivet i Stortinget</a> (64 fra Arbeiderpartiet,
 720 25 fra Høyre) er fortsatt aktive og argumenterer fortsatt for å radere
 721 vekk mer av innbyggernes privatsfære.</p>
 722
 723 <p>Når myndighetene demonstrerer sin mistillit til folket, tror jeg
 724 folket selv bør legge litt innsats i å verne sitt privatliv, ved å ta
 725 i bruk ende-til-ende-kryptert kommunikasjon med sine kjente og kjære,
 726 og begrense hvor mye privat informasjon som deles med uvedkommende.
 727 Det er jo ingenting som tyder på at myndighetene kommer til å være vår
 728 privatsfære.
 729 <a href="http://people.skolelinux.org/pere/blog/How_to_talk_with_your_loved_ones_in_private.html">Det
 730 er mange muligheter</a>.  Selv har jeg litt sans for
 731 <a href="https://ring.cx/">Ring</a>, som er basert på p2p-teknologi
 732 uten sentral kontroll, er fri programvare, og støtter meldinger, tale
 733 og video.  Systemet er tilgjengelig ut av boksen fra
 734 <a href="https://tracker.debian.org/pkg/ring">Debian</a> og
 735 <a href="https://launchpad.net/ubuntu/+source/ring">Ubuntu</a>, og det
 736 finnes pakker for Android, MacOSX og Windows.  Foreløpig er det få
 737 brukere med Ring, slik at jeg også bruker
 738 <a href="https://signal.org/">Signal</a> som nettleserutvidelse.</p>
 739 </div>
 740       <div class="tags">
 741
 742
 743         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>.
 744
 745
 746       </div>
 747     </div>
 748     <div class="padding"></div>
 749
 750     <div class="entry">
 751       <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>
 752       <div class="date"> 9th August 2017</div>
 753       <div class="body"><p>On friday, I came across an interesting article in the Norwegian
 754 web based ICT news magazine digi.no on
 755 <a href="https://www.digi.no/artikler/sikkerhetsforsker-lagde-enkel-imsi-catcher-for-60-kroner-na-kan-mobiler-kartlegges-av-alle/398588">how
 756 to collect the IMSI numbers of nearby cell phones</a> using the cheap
 757 DVB-T software defined radios.  The article refered to instructions
 758 and <a href="https://www.youtube.com/watch?v=UjwgNd_as30">a recipe by
 759 Keld Norman on Youtube on how to make a simple $7 IMSI Catcher</a>, and I decided to test them out.</p>
 760
 761 <p>The instructions said to use Ubuntu, install pip using apt (to
 762 bypass apt), use pip to install pybombs (to bypass both apt and pip),
 763 and the ask pybombs to fetch and build everything you need from
 764 scratch.  I wanted to see if I could do the same on the most recent
 765 Debian packages, but this did not work because pybombs tried to build
 766 stuff that no longer build with the most recent openssl library or
 767 some other version skew problem.  While trying to get this recipe
 768 working, I learned that the apt->pip->pybombs route was a long detour,
 769 and the only piece of software dependency missing in Debian was the
 770 gr-gsm package.  I also found out that the lead upstream developer of
 771 gr-gsm (the name stand for GNU Radio GSM) project already had a set of
 772 Debian packages provided in an Ubuntu PPA repository.  All I needed to
 773 do was to dget the Debian source package and built it.</p>
 774
 775 <p>The IMSI collector is a python script listening for packages on the
 776 loopback network device and printing to the terminal some specific GSM
 777 packages with IMSI numbers in them.  The code is fairly short and easy
 778 to understand.  The reason this work is because gr-gsm include a tool
 779 to read GSM data from a software defined radio like a DVB-T USB stick
 780 and other software defined radios, decode them and inject them into a
 781 network device on your Linux machine (using the loopback device by
 782 default).  This proved to work just fine, and I've been testing the
 783 collector for a few days now.</p>
 784
 785 <p>The updated and simpler recipe is thus to</p>
 786
 787 <ol>
 788
 789 <li>start with a Debian machine running Stretch or newer,</li>
 790
 791 <li>build and install the gr-gsm package available from
 792 <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>
 793
 794 <li>clone the git repostory from <a href="https://github.com/Oros42/IMSI-catcher">https://github.com/Oros42/IMSI-catcher</a>,</li>
 795
 796 <li>run grgsm_livemon and adjust the frequency until the terminal
 797 where it was started is filled with a stream of text (meaning you
 798 found a GSM station).</li>
 799
 800 <li>go into the IMSI-catcher directory and run 'sudo python simple_IMSI-catcher.py' to extract the IMSI numbers.</li>
 801
 802 </ol>
 803
 804 <p>To make it even easier in the future to get this sniffer up and
 805 running, I decided to package
 806 <a href="https://github.com/ptrkrysik/gr-gsm/">the gr-gsm project</a>
 807 for Debian (<a href="https://bugs.debian.org/871055">WNPP
 808 #871055</a>), and the package was uploaded into the NEW queue today.
 809 Luckily the gnuradio maintainer has promised to help me, as I do not
 810 know much about gnuradio stuff yet.</p>
 811
 812 <p>I doubt this "IMSI cacher" is anywhere near as powerfull as
 813 commercial tools like
 814 <a href="https://www.thespyphone.com/portable-imsi-imei-catcher/">The
 815 Spy Phone Portable IMSI / IMEI Catcher</a> or the
 816 <a href="https://en.wikipedia.org/wiki/Stingray_phone_tracker">Harris
 817 Stingray</a>, but I hope the existance of cheap alternatives can make
 818 more people realise how their whereabouts when carrying a cell phone
 819 is easily tracked.  Seeing the data flow on the screen, realizing that
 820 I live close to a police station and knowing that the police is also
 821 wearing cell phones, I wonder how hard it would be for criminals to
 822 track the position of the police officers to discover when there are
 823 police near by, or for foreign military forces to track the location
 824 of the Norwegian military forces, or for anyone to track the location
 825 of government officials...</p>
 826
 827 <p>It is worth noting that the data reported by the IMSI-catcher
 828 script mentioned above is only a fraction of the data broadcasted on
 829 the GSM network.  It will only collect one frequency at the time,
 830 while a typical phone will be using several frequencies, and not all
 831 phones will be using the frequencies tracked by the grgsm_livemod
 832 program.  Also, there is a lot of radio chatter being ignored by the
 833 simple_IMSI-catcher script, which would be collected by extending the
 834 parser code.  I wonder if gr-gsm can be set up to listen to more than
 835 one frequency?</p>
 836 </div>
 837       <div class="tags">
 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/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>.
 841
 842
 843       </div>
 844     </div>
 845     <div class="padding"></div>
 846
 847     <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>
 848     <div id="sidebar">
 849
 850
 851
 852 <h2>Archive</h2>
 853 <ul>
 854
 855 <li>2017
 856 <ul>
 857
 858 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/01/">January (4)</a></li>
 859
 860 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/02/">February (3)</a></li>
 861
 862 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/03/">March (5)</a></li>
 863
 864 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/04/">April (2)</a></li>
 865
 866 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/06/">June (5)</a></li>
 867
 868 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/07/">July (1)</a></li>
 869
 870 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/08/">August (1)</a></li>
 871
 872 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/09/">September (3)</a></li>
 873
 874 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/10/">October (5)</a></li>
 875
 876 <li><a href="http://people.skolelinux.org/pere/blog/archive/2017/11/">November (1)</a></li>
 877
 878 </ul></li>
 879
 880 <li>2016
 881 <ul>
 882
 883 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/01/">January (3)</a></li>
 884
 885 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/02/">February (2)</a></li>
 886
 887 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/03/">March (3)</a></li>
 888
 889 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/04/">April (8)</a></li>
 890
 891 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/05/">May (8)</a></li>
 892
 893 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/06/">June (2)</a></li>
 894
 895 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/07/">July (2)</a></li>
 896
 897 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/08/">August (5)</a></li>
 898
 899 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/09/">September (2)</a></li>
 900
 901 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/10/">October (3)</a></li>
 902
 903 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/11/">November (8)</a></li>
 904
 905 <li><a href="http://people.skolelinux.org/pere/blog/archive/2016/12/">December (5)</a></li>
 906
 907 </ul></li>
 908
 909 <li>2015
 910 <ul>
 911
 912 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/01/">January (7)</a></li>
 913
 914 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/02/">February (6)</a></li>
 915
 916 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/03/">March (1)</a></li>
 917
 918 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/04/">April (4)</a></li>
 919
 920 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/05/">May (3)</a></li>
 921
 922 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/06/">June (4)</a></li>
 923
 924 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/07/">July (6)</a></li>
 925
 926 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/08/">August (2)</a></li>
 927
 928 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/09/">September (2)</a></li>
 929
 930 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/10/">October (9)</a></li>
 931
 932 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/11/">November (6)</a></li>
 933
 934 <li><a href="http://people.skolelinux.org/pere/blog/archive/2015/12/">December (3)</a></li>
 935
 936 </ul></li>
 937
 938 <li>2014
 939 <ul>
 940
 941 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
 942
 943 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
 944
 945 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
 946
 947 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
 948
 949 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
 950
 951 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
 952
 953 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
 954
 955 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
 956
 957 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/09/">September (5)</a></li>
 958
 959 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/10/">October (6)</a></li>
 960
 961 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/11/">November (3)</a></li>
 962
 963 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/12/">December (5)</a></li>
 964
 965 </ul></li>
 966
 967 <li>2013
 968 <ul>
 969
 970 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 971
 972 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 973
 974 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 975
 976 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 977
 978 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 979
 980 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 981
 982 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 983
 984 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 985
 986 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 987
 988 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 989
 990 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
 991
 992 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
 993
 994 </ul></li>
 995
 996 <li>2012
 997 <ul>
 998
 999 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
1000
1001 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
1002
1003 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
1004
1005 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
1006
1007 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
1008
1009 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
1010
1011 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
1012
1013 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
1014
1015 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
1016
1017 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
1018
1019 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
1020
1021 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
1022
1023 </ul></li>
1024
1025 <li>2011
1026 <ul>
1027
1028 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
1029
1030 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
1031
1032 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
1033
1034 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
1035
1036 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
1037
1038 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
1039
1040 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
1041
1042 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
1043
1044 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
1045
1046 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
1047
1048 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
1049
1050 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
1051
1052 </ul></li>
1053
1054 <li>2010
1055 <ul>
1056
1057 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
1058
1059 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
1060
1061 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
1062
1063 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
1064
1065 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
1066
1067 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
1068
1069 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
1070
1071 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
1072
1073 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
1074
1075 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
1076
1077 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
1078
1079 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
1080
1081 </ul></li>
1082
1083 <li>2009
1084 <ul>
1085
1086 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
1087
1088 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
1089
1090 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
1091
1092 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
1093
1094 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
1095
1096 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
1097
1098 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
1099
1100 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
1101
1102 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
1103
1104 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
1105
1106 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
1107
1108 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
1109
1110 </ul></li>
1111
1112 <li>2008
1113 <ul>
1114
1115 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
1116
1117 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
1118
1119 </ul></li>
1120
1121 </ul>
1122
1123
1124
1125 <h2>Tags</h2>
1126 <ul>
1127
1128  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (14)</a></li>
1129
1130  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
1131
1132  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
1133
1134  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
1135
1136  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (9)</a></li>
1137
1138  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (16)</a></li>
1139
1140  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
1141
1142  <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
1143
1144  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (154)</a></li>
1145
1146  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (158)</a></li>
1147
1148  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian-handbook">debian-handbook (4)</a></li>
1149
1150  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
1151
1152  <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (17)</a></li>
1153
1154  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (24)</a></li>
1155
1156  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
1157
1158  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (358)</a></li>
1159
1160  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (23)</a></li>
1161
1162  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
1163
1164  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (30)</a></li>
1165
1166  <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (9)</a></li>
1167
1168  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (18)</a></li>
1169
1170  <li><a href="http://people.skolelinux.org/pere/blog/tags/h264">h264 (20)</a></li>
1171
1172  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (42)</a></li>
1173
1174  <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (15)</a></li>
1175
1176  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (20)</a></li>
1177
1178  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
1179
1180  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
1181
1182  <li><a href="http://people.skolelinux.org/pere/blog/tags/lsdvd">lsdvd (2)</a></li>
1183
1184  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
1185
1186  <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
1187
1188  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (39)</a></li>
1189
1190  <li><a href="http://people.skolelinux.org/pere/blog/tags/nice free software">nice free software (9)</a></li>
1191
1192  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (293)</a></li>
1193
1194  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (189)</a></li>
1195
1196  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (33)</a></li>
1197
1198  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
1199
1200  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (65)</a></li>
1201
1202  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (104)</a></li>
1203
1204  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (2)</a></li>
1205
1206  <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
1207
1208  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
1209
1210  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
1211
1212  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (10)</a></li>
1213
1214  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
1215
1216  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (5)</a></li>
1217
1218  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
1219
1220  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (53)</a></li>
1221
1222  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
1223
1224  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (5)</a></li>
1225
1226  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (55)</a></li>
1227
1228  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (6)</a></li>
1229
1230  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (12)</a></li>
1231
1232  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (52)</a></li>
1233
1234  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (4)</a></li>
1235
1236  <li><a href="http://people.skolelinux.org/pere/blog/tags/usenix">usenix (2)</a></li>
1237
1238  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (9)</a></li>
1239
1240  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (59)</a></li>
1241
1242  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
1243
1244  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (40)</a></li>
1245
1246 </ul>
1247
1248
1249     </div>
1250     <p style="text-align: right">
1251  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
1252 </p>
1253
1254   </body>
1255 </html>