blog/archive/2014/09/index.html

   1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
   2           "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
   3 <html xmlns="http://www.w3.org/1999/xhtml" dir="ltr">
   4   <head>
   5     <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
   6     <title>Petter Reinholdtsen: entries from September 2014</title>
   7     <link rel="stylesheet" type="text/css" media="screen" href="http://people.skolelinux.org/pere/blog/style.css" />
   8     <link rel="stylesheet" type="text/css" media="screen" href="http://people.skolelinux.org/pere/blog/vim.css" />
   9     <link rel="alternate" title="RSS Feed" href="09.rss" type="application/rss+xml" />
  10   </head>
  11   <body>
  12     <!-- XML FEED -->
  13     <div class="title">
  14  <h1>
  15      <a href="http://people.skolelinux.org/pere/blog/">Petter Reinholdtsen</a>
  16
  17  </h1>
  18
  19 </div>
  20
  21
  22     <h3>Entries from September 2014.</h3>
  23
  24     <div class="entry">
  25       <div class="title">
  26         <a href="http://people.skolelinux.org/pere/blog/Suddenly_I_am_the_new_upstream_of_the_lsdvd_command_line_tool.html">Suddenly I am the new upstream of the lsdvd command line tool</a>
  27       </div>
  28       <div class="date">
  29         25th September 2014
  30       </div>
  31       <div class="body">
  32         <p>I use the <a href="https://sourceforge.net/p/lsdvd/">lsdvd tool</a>
  33 to handle my fairly large DVD collection.  It is a nice command line
  34 tool to get details about a DVD, like title, tracks, track length,
  35 etc, in XML, Perl or human readable format.  But lsdvd have not seen
  36 any new development since 2006 and had a few irritating bugs affecting
  37 its use with some DVDs.  Upstream seemed to be dead, and in January I
  38 sent a small probe asking for a version control repository for the
  39 project, without any reply.  But I use it regularly and would like to
  40 get <a href="https://packages.qa.debian.org/lsdvd">an updated version
  41 into Debian</a>.  So two weeks ago I tried harder to get in touch with
  42 the project admin, and after getting a reply from him explaining that
  43 he was no longer interested in the project, I asked if I could take
  44 over.  And yesterday, I became project admin.</p>
  45
  46 <p>I've been in touch with a Gentoo developer and the Debian
  47 maintainer interested in joining forces to maintain the upstream
  48 project, and I hope we can get a new release out fairly quickly,
  49 collecting the patches spread around on the internet into on place.
  50 I've added the relevant Debian patches to the freshly created git
  51 repository, and expect the Gentoo patches to make it too.  If you got
  52 a DVD collection and care about command line tools, check out
  53 <a href="https://sourceforge.net/p/lsdvd/git/ci/master/tree/">the git source</a> and join
  54 <a href="https://sourceforge.net/p/lsdvd/mailman/">the project mailing
  55 list</a>. :)</p>
  56
  57       </div>
  58       <div class="tags">
  59
  60
  61         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/multimedia">multimedia</a>.
  62
  63
  64       </div>
  65     </div>
  66     <div class="padding"></div>
  67
  68     <div class="entry">
  69       <div class="title">
  70         <a href="http://people.skolelinux.org/pere/blog/Hva_henger_under_skibrua_over_E16_p__Sollih_gda_.html">Hva henger under skibrua over E16 på Sollihøgda?</a>
  71       </div>
  72       <div class="date">
  73         21st September 2014
  74       </div>
  75       <div class="body">
  76         <p>Rundt omkring i Oslo og Østlandsområdet henger det bokser over
  77 veiene som jeg har lurt på hva gjør.  De har ut fra plassering og
  78 vinkling sett ut som bokser som sniffer ut et eller annet fra
  79 forbipasserende trafikk, men det har vært uklart for meg hva det er de
  80 leser av.  Her om dagen tok jeg bilde av en slik boks som henger under
  81 <a href="http://www.openstreetmap.no/?zoom=19&mlat=59.96396&mlon=10.34443&layers=B00000">ei
  82 skibru på Sollihøgda</a>:</p>
  83
  84 <p align="center"><img width="60%" src="http://people.skolelinux.org/pere/blog/images/2014-09-13-kapsch-sollihogda-crop.jpeg"></p>
  85
  86 <p>Boksen er tydelig merket «Kapsch >>>», logoen til
  87 <a href="http://www.kapsch.net/">det sveitsiske selskapet Kapsch</a> som
  88 blant annet lager sensorsystemer for veitrafikk.  Men de lager mye
  89 forskjellig, og jeg kjente ikke igjen boksen på utseendet etter en
  90 kjapp titt på produktlista til selskapet.</p>
  91
  92 <p>I og med at boksen henger over veien E16, en riksvei vedlikeholdt
  93 av Statens Vegvesen, så antok jeg at det burde være mulig å bruke
  94 REST-API-et som gir tilgang til vegvesenets database over veier,
  95 skilter og annet veirelatert til å finne ut hva i alle dager dette
  96 kunne være.  De har både
  97 <a href="https://www.vegvesen.no/nvdb/api/dokumentasjon/datakatalog">en
  98 datakatalog</a> og
  99 <a href="https://www.vegvesen.no/nvdb/api/dokumentasjon/sok">et
 100 søk</a>, der en kan søke etter ulike typer oppføringer innen for et
 101 gitt geografisk område.  Jeg laget et enkelt shell-script for å hente
 102 ut antall av en gitt type innenfor området skibrua dekker, og listet
 103 opp navnet på typene som ble funnet.  Orket ikke slå opp hvordan
 104 URL-koding av aktuelle strenger kunne gjøres mer generisk, og brukte
 105 en stygg sed-linje i stedet.</p>
 106
 107 <blockquote><pre>
 108 #!/bin/sh
 109 urlmap() {
 110     sed \
 111     -e 's/  / /g'   -e 's/{/%7B/g'  \
 112     -e 's/}/%7D/g'  -e 's/\[/%5B/g' \
 113     -e 's/\]/%5D/g' -e 's/ /%20/g'  \
 114     -e 's/,/%2C/g'  -e 's/\"/%22/g' \
 115     -e 's/:/%3A/g'
 116 }
 117
 118 lookup() {
 119     url="$1"
 120     curl -s -H 'Accept: application/vnd.vegvesen.nvdb-v1+xml' \
 121        "https://www.vegvesen.no/nvdb/api$url" | xmllint --format -
 122 }
 123
 124 for id in $(seq 1 874) ; do
 125     search="{
 126   lokasjon: {
 127     bbox: \"10.34425,59.96386,10.34458,59.96409\",
 128     srid: \"WGS84\"
 129   },
 130    objektTyper: [{
 131      id: $id, antall: 10
 132    }]
 133 }"
 134
 135     query=/sok?kriterie=$(echo $search | urlmap)
 136     if lookup "$query" |
 137     grep -q '&lt;totaltAntallReturnert>0&lt;'
 138     then
 139     :
 140     else
 141     echo $id
 142     lookup "/datakatalog/objekttyper/$id" |grep '^  &lt;navn>'
 143     fi
 144 done
 145
 146 exit 0
 147 </pre></blockquote>
 148
 149 Aktuelt ID-område 1-874 var riktig i datakatalogen da jeg laget
 150 scriptet.  Det vil endre seg over tid.  Skriptet listet så opp
 151 aktuelle typer i og rundt skibrua:
 152
 153 <blockquote><pre>
 154 5
 155   &lt;navn>Rekkverk&lt;/navn>
 156 14
 157   &lt;navn>Rekkverksende&lt;/navn>
 158 47
 159   &lt;navn>Trafikklomme&lt;/navn>
 160 49
 161   &lt;navn>Trafikkøy&lt;/navn>
 162 60
 163   &lt;navn>Bru&lt;/navn>
 164 79
 165   &lt;navn>Stikkrenne/Kulvert&lt;/navn>
 166 80
 167   &lt;navn>Grøft, åpen&lt;/navn>
 168 86
 169   &lt;navn>Belysningsstrekning&lt;/navn>
 170 95
 171   &lt;navn>Skiltpunkt&lt;/navn>
 172 96
 173   &lt;navn>Skiltplate&lt;/navn>
 174 98
 175   &lt;navn>Referansestolpe&lt;/navn>
 176 99
 177   &lt;navn>Vegoppmerking, langsgående&lt;/navn>
 178 105
 179   &lt;navn>Fartsgrense&lt;/navn>
 180 106
 181   &lt;navn>Vinterdriftsstrategi&lt;/navn>
 182 172
 183   &lt;navn>Trafikkdeler&lt;/navn>
 184 241
 185   &lt;navn>Vegdekke&lt;/navn>
 186 293
 187   &lt;navn>Breddemåling&lt;/navn>
 188 301
 189   &lt;navn>Kantklippareal&lt;/navn>
 190 318
 191   &lt;navn>Snø-/isrydding&lt;/navn>
 192 445
 193   &lt;navn>Skred&lt;/navn>
 194 446
 195   &lt;navn>Dokumentasjon&lt;/navn>
 196 452
 197   &lt;navn>Undergang&lt;/navn>
 198 528
 199   &lt;navn>Tverrprofil&lt;/navn>
 200 532
 201   &lt;navn>Vegreferanse&lt;/navn>
 202 534
 203   &lt;navn>Region&lt;/navn>
 204 535
 205   &lt;navn>Fylke&lt;/navn>
 206 536
 207   &lt;navn>Kommune&lt;/navn>
 208 538
 209   &lt;navn>Gate&lt;/navn>
 210 539
 211   &lt;navn>Transportlenke&lt;/navn>
 212 540
 213   &lt;navn>Trafikkmengde&lt;/navn>
 214 570
 215   &lt;navn>Trafikkulykke&lt;/navn>
 216 571
 217   &lt;navn>Ulykkesinvolvert enhet&lt;/navn>
 218 572
 219   &lt;navn>Ulykkesinvolvert person&lt;/navn>
 220 579
 221   &lt;navn>Politidistrikt&lt;/navn>
 222 583
 223   &lt;navn>Vegbredde&lt;/navn>
 224 591
 225   &lt;navn>Høydebegrensning&lt;/navn>
 226 592
 227   &lt;navn>Nedbøyningsmåling&lt;/navn>
 228 597
 229   &lt;navn>Støy-luft, Strekningsdata&lt;/navn>
 230 601
 231   &lt;navn>Oppgravingsdata&lt;/navn>
 232 602
 233   &lt;navn>Oppgravingslag&lt;/navn>
 234 603
 235   &lt;navn>PMS-parsell&lt;/navn>
 236 604
 237   &lt;navn>Vegnormalstrekning&lt;/navn>
 238 605
 239   &lt;navn>Værrelatert strekning&lt;/navn>
 240 616
 241   &lt;navn>Feltstrekning&lt;/navn>
 242 617
 243   &lt;navn>Adressepunkt&lt;/navn>
 244 626
 245   &lt;navn>Friksjonsmåleserie&lt;/navn>
 246 629
 247   &lt;navn>Vegdekke, flatelapping&lt;/navn>
 248 639
 249   &lt;navn>Kurvatur, horisontalelement&lt;/navn>
 250 640
 251   &lt;navn>Kurvatur, vertikalelement&lt;/navn>
 252 642
 253   &lt;navn>Kurvatur, vertikalpunkt&lt;/navn>
 254 643
 255   &lt;navn>Statistikk, trafikkmengde&lt;/navn>
 256 647
 257   &lt;navn>Statistikk, vegbredde&lt;/navn>
 258 774
 259   &lt;navn>Nedbøyningsmåleserie&lt;/navn>
 260 775
 261   &lt;navn>ATK, influensstrekning&lt;/navn>
 262 794
 263   &lt;navn>Systemobjekt&lt;/navn>
 264 810
 265   &lt;navn>Vinterdriftsklasse&lt;/navn>
 266 821
 267   &lt;navn>Funksjonell vegklasse&lt;/navn>
 268 825
 269   &lt;navn>Kurvatur, stigning&lt;/navn>
 270 838
 271   &lt;navn>Vegbredde, beregnet&lt;/navn>
 272 862
 273   &lt;navn>Reisetidsregistreringspunkt&lt;/navn>
 274 871
 275   &lt;navn>Bruksklasse&lt;/navn>
 276 </pre></blockquote>
 277
 278 <p>Av disse ser ID 775 og 862 mest relevant ut.  ID 775 antar jeg
 279 refererer til fotoboksen som står like ved brua, mens
 280 «Reisetidsregistreringspunkt» kanskje kan være boksen som henger der.
 281 Hvordan finner jeg så ut hva dette kan være for noe.  En titt på
 282 <a href="http://labs.vegdata.no/nvdb-datakatalog/862-Reisetidsregistreringspunkt/">datakatalogsiden
 283 for ID 862/Reisetidsregistreringspunkt</a> viser at det er finnes 53
 284 slike målere i Norge, og hvor de er plassert, men gir ellers få
 285 detaljer.  Det er plassert 40 på østlandet og 13 i Trondheimsregionen.
 286 Men siden nevner «AutoPASS», og hvis en slår opp oppføringen på
 287 Sollihøgda nevner den «Ciber AS» som ID for eksternt system.  (Kan det
 288 være snakk om
 289 <a href="http://www.proff.no/selskap/ciber-norge-as/oslo/internettdesign-og-programmering/Z0I3KMF4/">Ciber
 290 Norge AS</a>, et selskap eid av Ciber Europe Bv?)  Et nettsøk på
 291  «Ciber AS autopass» fører meg til en artikkel fra NRK Trøndelag i
 292  2013 med tittel
 293 «<a href="http://www.nrk.no/trondelag/sjekk-dette-hvis-du-vil-unnga-ko-1.11327947">Sjekk
 294 dette hvis du vil unngå kø</a>».  Artikkelen henviser til vegvesenets
 295 nettside
 296 <a href="http://www.reisetider.no/reisetid/forside.html">reisetider.no</a>
 297 som har en
 298 <a href="http://www.reisetider.no/reisetid/omrade.html?omrade=5">kartside
 299 for Østlandet</a> som viser at det måles mellom Sandvika og Sollihøgda.
 300 Det kan dermed se ut til at jeg har funnet ut hva boksene gjør.</p>
 301
 302 <p>Hvis det stemmer, så er dette bokser som leser av AutoPASS-ID-en
 303 til alle passerende biler med AutoPASS-brikke, og dermed gjør det mulig
 304 for de som kontrollerer boksene å holde rede på hvor en gitt bil er
 305 når den passerte et slikt målepunkt.  NRK-artikkelen forteller at
 306 denne informasjonen i dag kun brukes til å koble to
 307 AutoPASS-brikkepasseringer passeringer sammen for å beregne
 308 reisetiden, og at bruken er godkjent av Datatilsynet.  Det er desverre
 309 ikke mulig for en sjåfør som passerer under en slik boks å kontrollere
 310 at AutoPASS-ID-en kun brukes til dette i dag og i fremtiden.</p>
 311
 312 <p>I tillegg til denne type AutoPASS-sniffere vet jeg at det også
 313 finnes mange automatiske stasjoner som tar betalt pr. passering (aka
 314 bomstasjoner), og der lagres informasjon om tid, sted og bilnummer i
 315 10 år.  Finnes det andre slike sniffere plassert ut på veiene?</p>
 316
 317 <p>Personlig har jeg valgt å ikke bruke AutoPASS-brikke, for å gjøre
 318 det vanskeligere og mer kostbart for de som vil invadere privatsfæren
 319 og holde rede på hvor bilen min beveger seg til enhver tid.  Jeg håper
 320 flere vil gjøre det samme, selv om det gir litt høyere private
 321 utgifter (dyrere bompassering).  Vern om privatsfæren koster i disse
 322 dager.</p>
 323
 324 <p>Takk til Jan Kristian Jensen i Statens Vegvesen for tips om
 325 dokumentasjon på vegvesenets REST-API.</p>
 326
 327       </div>
 328       <div class="tags">
 329
 330
 331         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/kart">kart</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/rfid">rfid</a>, <a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance</a>.
 332
 333
 334       </div>
 335     </div>
 336     <div class="padding"></div>
 337
 338     <div class="entry">
 339       <div class="title">
 340         <a href="http://people.skolelinux.org/pere/blog/Speeding_up_the_Debian_installer_using_eatmydata_and_dpkg_divert.html">Speeding up the Debian installer using eatmydata and dpkg-divert</a>
 341       </div>
 342       <div class="date">
 343         16th September 2014
 344       </div>
 345       <div class="body">
 346         <p>The <a href="https://www.debian.org/">Debian</a> installer could be
 347 a lot quicker.  When we install more than 2000 packages in
 348 <a href="http://www.skolelinux.org/">Skolelinux / Debian Edu</a> using
 349 tasksel in the installer, unpacking the binary packages take forever.
 350 A part of the slow I/O issue was discussed in
 351 <a href="https://bugs.debian.org/613428">bug #613428</a> about too
 352 much file system sync-ing done by dpkg, which is the package
 353 responsible for unpacking the binary packages.  Other parts (like code
 354 executed by postinst scripts) might also sync to disk during
 355 installation.  All this sync-ing to disk do not really make sense to
 356 me.  If the machine crash half-way through, I start over, I do not try
 357 to salvage the half installed system.  So the failure sync-ing is
 358 supposed to protect against, hardware or system crash, is not really
 359 relevant while the installer is running.</p>
 360
 361 <p>A few days ago, I thought of a way to get rid of all the file
 362 system sync()-ing in a fairly non-intrusive way, without the need to
 363 change the code in several packages.  The idea is not new, but I have
 364 not heard anyone propose the approach using dpkg-divert before.  It
 365 depend on the small and clever package
 366 <a href="https://packages.qa.debian.org/eatmydata">eatmydata</a>, which
 367 uses LD_PRELOAD to replace the system functions for syncing data to
 368 disk with functions doing nothing, thus allowing programs to live
 369 dangerous while speeding up disk I/O significantly.  Instead of
 370 modifying the implementation of dpkg, apt and tasksel (which are the
 371 packages responsible for selecting, fetching and installing packages),
 372 it occurred to me that we could just divert the programs away, replace
 373 them with a simple shell wrapper calling
 374 "eatmydata&nbsp;$program&nbsp;$@", to get the same effect.
 375 Two days ago I decided to test the idea, and wrapped up a simple
 376 implementation for the Debian Edu udeb.</p>
 377
 378 <p>The effect was stunning.  In my first test it reduced the running
 379 time of the pkgsel step (installing tasks) from 64 to less than 44
 380 minutes (20 minutes shaved off the installation) on an old Dell
 381 Latitude D505 machine.  I am not quite sure what the optimised time
 382 would have been, as I messed up the testing a bit, causing the debconf
 383 priority to get low enough for two questions to pop up during
 384 installation.  As soon as I saw the questions I moved the installation
 385 along, but do not know how long the question were holding up the
 386 installation.  I did some more measurements using Debian Edu Jessie,
 387 and got these results.  The time measured is the time stamp in
 388 /var/log/syslog between the "pkgsel: starting tasksel" and the
 389 "pkgsel: finishing up" lines, if you want to do the same measurement
 390 yourself.  In Debian Edu, the tasksel dialog do not show up, and the
 391 timing thus do not depend on how quickly the user handle the tasksel
 392 dialog.</p>
 393
 394 <p><table>
 395
 396 <tr>
 397 <th>Machine/setup</th>
 398 <th>Original tasksel</th>
 399 <th>Optimised tasksel</th>
 400 <th>Reduction</th>
 401 </tr>
 402
 403 <tr>
 404 <td>Latitude D505 Main+LTSP LXDE</td>
 405 <td>64 min (07:46-08:50)</td>
 406 <td><44 min (11:27-12:11)</td>
 407 <td>>20 min 18%</td>
 408 </tr>
 409
 410 <tr>
 411 <td>Latitude D505 Roaming LXDE</td>
 412 <td>57 min (08:48-09:45)</td>
 413 <td>34 min (07:43-08:17)</td>
 414 <td>23 min 40%</td>
 415 </tr>
 416
 417 <tr>
 418 <td>Latitude D505 Minimal</td>
 419 <td>22 min (10:37-10:59)</td>
 420 <td>11 min (11:16-11:27)</td>
 421 <td>11 min 50%</td>
 422 </tr>
 423
 424 <tr>
 425 <td>Thinkpad X200 Minimal</td>
 426 <td>6 min (08:19-08:25)</td>
 427 <td>4 min (08:04-08:08)</td>
 428 <td>2 min 33%</td>
 429 </tr>
 430
 431 <tr>
 432 <td>Thinkpad X200 Roaming KDE</td>
 433 <td>19 min (09:21-09:40)</td>
 434 <td>15 min (10:25-10:40)</td>
 435 <td>4 min 21%</td>
 436 </tr>
 437
 438 </table></p>
 439
 440 <p>The test is done using a netinst ISO on a USB stick, so some of the
 441 time is spent downloading packages.  The connection to the Internet
 442 was 100Mbit/s during testing, so downloading should not be a
 443 significant factor in the measurement.  Download typically took a few
 444 seconds to a few minutes, depending on the amount of packages being
 445 installed.</p>
 446
 447 <p>The speedup is implemented by using two hooks in
 448 <a href="https://www.debian.org/devel/debian-installer/">Debian
 449 Installer</a>, the pre-pkgsel.d hook to set up the diverts, and the
 450 finish-install.d hook to remove the divert at the end of the
 451 installation.  I picked the pre-pkgsel.d hook instead of the
 452 post-base-installer.d hook because I test using an ISO without the
 453 eatmydata package included, and the post-base-installer.d hook in
 454 Debian Edu can only operate on packages included in the ISO.  The
 455 negative effect of this is that I am unable to activate this
 456 optimization for the kernel installation step in d-i.  If the code is
 457 moved to the post-base-installer.d hook, the speedup would be larger
 458 for the entire installation.</p>
 459
 460 <p>I've implemented this in the
 461 <a href="https://packages.qa.debian.org/debian-edu-install">debian-edu-install</a>
 462 git repository, and plan to provide the optimization as part of the
 463 Debian Edu installation.  If you want to test this yourself, you can
 464 create two files in the installer (or in an udeb).  One shell script
 465 need do go into /usr/lib/pre-pkgsel.d/, with content like this:</p>
 466
 467 <p><blockquote><pre>
 468 #!/bin/sh
 469 set -e
 470 . /usr/share/debconf/confmodule
 471 info() {
 472     logger -t my-pkgsel "info: $*"
 473 }
 474 error() {
 475     logger -t my-pkgsel "error: $*"
 476 }
 477 override_install() {
 478     apt-install eatmydata || true
 479     if [ -x /target/usr/bin/eatmydata ] ; then
 480         for bin in dpkg apt-get aptitude tasksel ; do
 481             file=/usr/bin/$bin
 482             # Test that the file exist and have not been diverted already.
 483             if [ -f /target$file ] ; then
 484                 info "diverting $file using eatmydata"
 485                 printf "#!/bin/sh\neatmydata $bin.distrib \"\$@\"\n" \
 486                     > /target$file.edu
 487                 chmod 755 /target$file.edu
 488                 in-target dpkg-divert --package debian-edu-config \
 489                     --rename --quiet --add $file
 490                 ln -sf ./$bin.edu /target$file
 491             else
 492                 error "unable to divert $file, as it is missing."
 493             fi
 494         done
 495     else
 496         error "unable to find /usr/bin/eatmydata after installing the eatmydata pacage"
 497     fi
 498 }
 499
 500 override_install
 501 </pre></blockquote></p>
 502
 503 <p>To clean up, another shell script should go into
 504 /usr/lib/finish-install.d/ with code like this:
 505
 506 <p><blockquote><pre>
 507 #! /bin/sh -e
 508 . /usr/share/debconf/confmodule
 509 error() {
 510     logger -t my-finish-install "error: $@"
 511 }
 512 remove_install_override() {
 513     for bin in dpkg apt-get aptitude tasksel ; do
 514         file=/usr/bin/$bin
 515         if [ -x /target$file.edu ] ; then
 516             rm /target$file
 517             in-target dpkg-divert --package debian-edu-config \
 518                 --rename --quiet --remove $file
 519             rm /target$file.edu
 520         else
 521             error "Missing divert for $file."
 522         fi
 523     done
 524     sync # Flush file buffers before continuing
 525 }
 526
 527 remove_install_override
 528 </pre></blockquote></p>
 529
 530 <p>In Debian Edu, I placed both code fragments in a separate script
 531 edu-eatmydata-install and call it from the pre-pkgsel.d and
 532 finish-install.d scripts.</p>
 533
 534 <p>By now you might ask if this change should get into the normal
 535 Debian installer too?  I suspect it should, but am not sure the
 536 current debian-installer coordinators find it useful enough.  It also
 537 depend on the side effects of the change.  I'm not aware of any, but I
 538 guess we will see if the change is safe after some more testing.
 539 Perhaps there is some package in Debian depending on sync() and
 540 fsync() having effect?  Perhaps it should go into its own udeb, to
 541 allow those of us wanting to enable it to do so without affecting
 542 everyone.</p>
 543
 544 <p>Update 2014-09-24: Since a few days ago, enabling this optimization
 545 will break installation of all programs using gnutls because of
 546 <ahref="https://bugs.debian.org/702711">bug #702711.  An updated
 547 eatmydata package in Debian will solve it.</p>
 548
 549       </div>
 550       <div class="tags">
 551
 552
 553         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>.
 554
 555
 556       </div>
 557     </div>
 558     <div class="padding"></div>
 559
 560     <div class="entry">
 561       <div class="title">
 562         <a href="http://people.skolelinux.org/pere/blog/Good_bye_subkeys_pgp_net__welcome_pool_sks_keyservers_net.html">Good bye subkeys.pgp.net, welcome pool.sks-keyservers.net</a>
 563       </div>
 564       <div class="date">
 565         10th September 2014
 566       </div>
 567       <div class="body">
 568         <p>Yesterday, I had the pleasure of attending a talk with the
 569 <a href="http://www.nuug.no/">Norwegian Unix User Group</a> about
 570 <a href="http://www.nuug.no/aktiviteter/20140909-sks-keyservers/">the
 571 OpenPGP keyserver pool sks-keyservers.net</a>, and was very happy to
 572 learn that there is a large set of publicly available key servers to
 573 use when looking for peoples public key.  So far I have used
 574 subkeys.pgp.net, and some times wwwkeys.nl.pgp.net when the former
 575 were misbehaving, but those days are ended.  The servers I have used
 576 up until yesterday have been slow and some times unavailable.  I hope
 577 those problems are gone now.</p>
 578
 579 <p>Behind the round robin DNS entry of the
 580 <a href="https://sks-keyservers.net/">sks-keyservers.net</a> service
 581 there is a pool of more than 100 keyservers which are checked every
 582 day to ensure they are well connected and up to date.  It must be
 583 better than what I have used so far. :)</p>
 584
 585 <p>Yesterdays speaker told me that the service is the default
 586 keyserver provided by the default configuration in GnuPG, but this do
 587 not seem to be used in Debian.  Perhaps it should?</p>
 588
 589 <p>Anyway, I've updated my ~/.gnupg/options file to now include this
 590 line:</p>
 591
 592 <p><blockquote><pre>
 593 keyserver pool.sks-keyservers.net
 594 </pre></blockquote></p>
 595
 596 <p>With GnuPG version 2 one can also locate the keyserver using SRV
 597 entries in DNS.  Just for fun, I did just that at work, so now every
 598 user of GnuPG at the University of Oslo should find a OpenGPG
 599 keyserver automatically should their need it:</p>
 600
 601 <p><blockquote><pre>
 602 % host -t srv _pgpkey-http._tcp.uio.no
 603 _pgpkey-http._tcp.uio.no has SRV record 0 100 11371 pool.sks-keyservers.net.
 604 %
 605 </pre></blockquote></p>
 606
 607 <p>Now if only
 608 <a href="http://ietfreport.isoc.org/idref/draft-shaw-openpgp-hkp/">the
 609 HKP lookup protocol</a> supported finding signature paths, I would be
 610 very happy.  It can look up a given key or search for a user ID, but I
 611 normally do not want that, but to find a trust path from my key to
 612 another key.  Given a user ID or key ID, I would like to find (and
 613 download) the keys representing a signature path from my key to the
 614 key in question, to be able to get a trust path between the two keys.
 615 This is as far as I can tell not possible today.  Perhaps something
 616 for a future version of the protocol?</p>
 617
 618       </div>
 619       <div class="tags">
 620
 621
 622         Tags: <a href="http://people.skolelinux.org/pere/blog/tags/debian">debian</a>, <a href="http://people.skolelinux.org/pere/blog/tags/english">english</a>, <a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern</a>, <a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet</a>.
 623
 624
 625       </div>
 626     </div>
 627     <div class="padding"></div>
 628
 629     <p style="text-align: right;"><a href="09.rss"><img src="http://people.skolelinux.org/pere/blog/xml.gif" alt="RSS Feed" width="36" height="14" /></a></p>
 630     <div id="sidebar">
 631
 632
 633
 634 <h2>Archive</h2>
 635 <ul>
 636
 637 <li>2014
 638 <ul>
 639
 640 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/01/">January (2)</a></li>
 641
 642 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/02/">February (3)</a></li>
 643
 644 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/03/">March (8)</a></li>
 645
 646 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/04/">April (7)</a></li>
 647
 648 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/05/">May (1)</a></li>
 649
 650 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/06/">June (2)</a></li>
 651
 652 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/07/">July (2)</a></li>
 653
 654 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/08/">August (2)</a></li>
 655
 656 <li><a href="http://people.skolelinux.org/pere/blog/archive/2014/09/">September (4)</a></li>
 657
 658 </ul></li>
 659
 660 <li>2013
 661 <ul>
 662
 663 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/01/">January (11)</a></li>
 664
 665 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/02/">February (9)</a></li>
 666
 667 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/03/">March (9)</a></li>
 668
 669 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/04/">April (6)</a></li>
 670
 671 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/05/">May (9)</a></li>
 672
 673 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/06/">June (10)</a></li>
 674
 675 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/07/">July (7)</a></li>
 676
 677 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/08/">August (3)</a></li>
 678
 679 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/09/">September (5)</a></li>
 680
 681 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/10/">October (7)</a></li>
 682
 683 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/11/">November (9)</a></li>
 684
 685 <li><a href="http://people.skolelinux.org/pere/blog/archive/2013/12/">December (3)</a></li>
 686
 687 </ul></li>
 688
 689 <li>2012
 690 <ul>
 691
 692 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/01/">January (7)</a></li>
 693
 694 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/02/">February (10)</a></li>
 695
 696 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/03/">March (17)</a></li>
 697
 698 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/04/">April (12)</a></li>
 699
 700 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/05/">May (12)</a></li>
 701
 702 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/06/">June (20)</a></li>
 703
 704 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/07/">July (17)</a></li>
 705
 706 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/08/">August (6)</a></li>
 707
 708 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/09/">September (9)</a></li>
 709
 710 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/10/">October (17)</a></li>
 711
 712 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/11/">November (10)</a></li>
 713
 714 <li><a href="http://people.skolelinux.org/pere/blog/archive/2012/12/">December (7)</a></li>
 715
 716 </ul></li>
 717
 718 <li>2011
 719 <ul>
 720
 721 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/01/">January (16)</a></li>
 722
 723 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/02/">February (6)</a></li>
 724
 725 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/03/">March (6)</a></li>
 726
 727 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/04/">April (7)</a></li>
 728
 729 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/05/">May (3)</a></li>
 730
 731 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/06/">June (2)</a></li>
 732
 733 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/07/">July (7)</a></li>
 734
 735 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/08/">August (6)</a></li>
 736
 737 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/09/">September (4)</a></li>
 738
 739 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/10/">October (2)</a></li>
 740
 741 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/11/">November (3)</a></li>
 742
 743 <li><a href="http://people.skolelinux.org/pere/blog/archive/2011/12/">December (1)</a></li>
 744
 745 </ul></li>
 746
 747 <li>2010
 748 <ul>
 749
 750 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/01/">January (2)</a></li>
 751
 752 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/02/">February (1)</a></li>
 753
 754 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/03/">March (3)</a></li>
 755
 756 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/04/">April (3)</a></li>
 757
 758 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/05/">May (9)</a></li>
 759
 760 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/06/">June (14)</a></li>
 761
 762 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/07/">July (12)</a></li>
 763
 764 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/08/">August (13)</a></li>
 765
 766 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/09/">September (7)</a></li>
 767
 768 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/10/">October (9)</a></li>
 769
 770 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/11/">November (13)</a></li>
 771
 772 <li><a href="http://people.skolelinux.org/pere/blog/archive/2010/12/">December (12)</a></li>
 773
 774 </ul></li>
 775
 776 <li>2009
 777 <ul>
 778
 779 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/01/">January (8)</a></li>
 780
 781 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/02/">February (8)</a></li>
 782
 783 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/03/">March (12)</a></li>
 784
 785 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/04/">April (10)</a></li>
 786
 787 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/05/">May (9)</a></li>
 788
 789 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/06/">June (3)</a></li>
 790
 791 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/07/">July (4)</a></li>
 792
 793 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/08/">August (3)</a></li>
 794
 795 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/09/">September (1)</a></li>
 796
 797 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/10/">October (2)</a></li>
 798
 799 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/11/">November (3)</a></li>
 800
 801 <li><a href="http://people.skolelinux.org/pere/blog/archive/2009/12/">December (3)</a></li>
 802
 803 </ul></li>
 804
 805 <li>2008
 806 <ul>
 807
 808 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/11/">November (5)</a></li>
 809
 810 <li><a href="http://people.skolelinux.org/pere/blog/archive/2008/12/">December (7)</a></li>
 811
 812 </ul></li>
 813
 814 </ul>
 815
 816
 817
 818 <h2>Tags</h2>
 819 <ul>
 820
 821  <li><a href="http://people.skolelinux.org/pere/blog/tags/3d-printer">3d-printer (13)</a></li>
 822
 823  <li><a href="http://people.skolelinux.org/pere/blog/tags/amiga">amiga (1)</a></li>
 824
 825  <li><a href="http://people.skolelinux.org/pere/blog/tags/aros">aros (1)</a></li>
 826
 827  <li><a href="http://people.skolelinux.org/pere/blog/tags/bankid">bankid (4)</a></li>
 828
 829  <li><a href="http://people.skolelinux.org/pere/blog/tags/bitcoin">bitcoin (8)</a></li>
 830
 831  <li><a href="http://people.skolelinux.org/pere/blog/tags/bootsystem">bootsystem (14)</a></li>
 832
 833  <li><a href="http://people.skolelinux.org/pere/blog/tags/bsa">bsa (2)</a></li>
 834
 835  <li><a href="http://people.skolelinux.org/pere/blog/tags/chrpath">chrpath (2)</a></li>
 836
 837  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian">debian (102)</a></li>
 838
 839  <li><a href="http://people.skolelinux.org/pere/blog/tags/debian edu">debian edu (149)</a></li>
 840
 841  <li><a href="http://people.skolelinux.org/pere/blog/tags/digistan">digistan (10)</a></li>
 842
 843  <li><a href="http://people.skolelinux.org/pere/blog/tags/dld">dld (15)</a></li>
 844
 845  <li><a href="http://people.skolelinux.org/pere/blog/tags/docbook">docbook (12)</a></li>
 846
 847  <li><a href="http://people.skolelinux.org/pere/blog/tags/drivstoffpriser">drivstoffpriser (4)</a></li>
 848
 849  <li><a href="http://people.skolelinux.org/pere/blog/tags/english">english (254)</a></li>
 850
 851  <li><a href="http://people.skolelinux.org/pere/blog/tags/fiksgatami">fiksgatami (21)</a></li>
 852
 853  <li><a href="http://people.skolelinux.org/pere/blog/tags/fildeling">fildeling (12)</a></li>
 854
 855  <li><a href="http://people.skolelinux.org/pere/blog/tags/freeculture">freeculture (13)</a></li>
 856
 857  <li><a href="http://people.skolelinux.org/pere/blog/tags/freedombox">freedombox (8)</a></li>
 858
 859  <li><a href="http://people.skolelinux.org/pere/blog/tags/frikanalen">frikanalen (11)</a></li>
 860
 861  <li><a href="http://people.skolelinux.org/pere/blog/tags/intervju">intervju (41)</a></li>
 862
 863  <li><a href="http://people.skolelinux.org/pere/blog/tags/isenkram">isenkram (9)</a></li>
 864
 865  <li><a href="http://people.skolelinux.org/pere/blog/tags/kart">kart (19)</a></li>
 866
 867  <li><a href="http://people.skolelinux.org/pere/blog/tags/ldap">ldap (9)</a></li>
 868
 869  <li><a href="http://people.skolelinux.org/pere/blog/tags/lenker">lenker (8)</a></li>
 870
 871  <li><a href="http://people.skolelinux.org/pere/blog/tags/ltsp">ltsp (1)</a></li>
 872
 873  <li><a href="http://people.skolelinux.org/pere/blog/tags/mesh network">mesh network (8)</a></li>
 874
 875  <li><a href="http://people.skolelinux.org/pere/blog/tags/multimedia">multimedia (30)</a></li>
 876
 877  <li><a href="http://people.skolelinux.org/pere/blog/tags/norsk">norsk (248)</a></li>
 878
 879  <li><a href="http://people.skolelinux.org/pere/blog/tags/nuug">nuug (162)</a></li>
 880
 881  <li><a href="http://people.skolelinux.org/pere/blog/tags/offentlig innsyn">offentlig innsyn (11)</a></li>
 882
 883  <li><a href="http://people.skolelinux.org/pere/blog/tags/open311">open311 (2)</a></li>
 884
 885  <li><a href="http://people.skolelinux.org/pere/blog/tags/opphavsrett">opphavsrett (48)</a></li>
 886
 887  <li><a href="http://people.skolelinux.org/pere/blog/tags/personvern">personvern (75)</a></li>
 888
 889  <li><a href="http://people.skolelinux.org/pere/blog/tags/raid">raid (1)</a></li>
 890
 891  <li><a href="http://people.skolelinux.org/pere/blog/tags/reactos">reactos (1)</a></li>
 892
 893  <li><a href="http://people.skolelinux.org/pere/blog/tags/reprap">reprap (11)</a></li>
 894
 895  <li><a href="http://people.skolelinux.org/pere/blog/tags/rfid">rfid (3)</a></li>
 896
 897  <li><a href="http://people.skolelinux.org/pere/blog/tags/robot">robot (9)</a></li>
 898
 899  <li><a href="http://people.skolelinux.org/pere/blog/tags/rss">rss (1)</a></li>
 900
 901  <li><a href="http://people.skolelinux.org/pere/blog/tags/ruter">ruter (4)</a></li>
 902
 903  <li><a href="http://people.skolelinux.org/pere/blog/tags/scraperwiki">scraperwiki (2)</a></li>
 904
 905  <li><a href="http://people.skolelinux.org/pere/blog/tags/sikkerhet">sikkerhet (41)</a></li>
 906
 907  <li><a href="http://people.skolelinux.org/pere/blog/tags/sitesummary">sitesummary (4)</a></li>
 908
 909  <li><a href="http://people.skolelinux.org/pere/blog/tags/skepsis">skepsis (4)</a></li>
 910
 911  <li><a href="http://people.skolelinux.org/pere/blog/tags/standard">standard (45)</a></li>
 912
 913  <li><a href="http://people.skolelinux.org/pere/blog/tags/stavekontroll">stavekontroll (3)</a></li>
 914
 915  <li><a href="http://people.skolelinux.org/pere/blog/tags/stortinget">stortinget (9)</a></li>
 916
 917  <li><a href="http://people.skolelinux.org/pere/blog/tags/surveillance">surveillance (26)</a></li>
 918
 919  <li><a href="http://people.skolelinux.org/pere/blog/tags/sysadmin">sysadmin (1)</a></li>
 920
 921  <li><a href="http://people.skolelinux.org/pere/blog/tags/valg">valg (8)</a></li>
 922
 923  <li><a href="http://people.skolelinux.org/pere/blog/tags/video">video (43)</a></li>
 924
 925  <li><a href="http://people.skolelinux.org/pere/blog/tags/vitenskap">vitenskap (4)</a></li>
 926
 927  <li><a href="http://people.skolelinux.org/pere/blog/tags/web">web (33)</a></li>
 928
 929 </ul>
 930
 931
 932     </div>
 933     <p style="text-align: right">
 934  Created by <a href="http://steve.org.uk/Software/chronicle">Chronicle v4.6</a>
 935 </p>
 936
 937   </body>
 938 </html>