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<rss version='2.0' xmlns:lj='http://www.livejournal.org/rss/lj/1.0/'>
        <channel>
                <title>Petter Reinholdtsen - Entries from September 2014</title>
                <description>Entries from September 2014</description>
                <link>http://www.hungry.com/~pere/blog/</link>

        
        <item>
                <title>How to test Debian Edu Jessie despite some fatal problems with the installer</title>
                <link>http://www.hungry.com/~pere/blog/How_to_test_Debian_Edu_Jessie_despite_some_fatal_problems_with_the_installer.html</link>        
                <guid isPermaLink="true">http://www.hungry.com/~pere/blog/How_to_test_Debian_Edu_Jessie_despite_some_fatal_problems_with_the_installer.html</guid>
                <pubDate>Fri, 26 Sep 2014 12:20:00 +0200</pubDate>
                <description>&lt;p&gt;The &lt;a href=&quot;http://www.skolelinux.org/&quot;&gt;Debian Edu / Skolelinux
project&lt;/a&gt; provide a Linux solution for schools, including a
powerful desktop with education software, a central server providing
web pages, user database, user home directories, central login and PXE
boot of both  clients without disk and the installation to install Debian
Edu on machines with disk (and a few other services perhaps to small
to mention here).  We in the Debian Edu team are currently working on
the Jessie based version, trying to get everything in shape before the
freeze, to avoid having to maintain our own package repository in the
future.  The
&lt;a href=&quot;https://wiki.debian.org/DebianEdu/Status/Jessie&quot;&gt;current
status&lt;/a&gt; can be seen on the Debian wiki, and there is still heaps of
work left.  Some fatal problems block testing, breaking the installer,
but it is possible to work around these to get anyway.  Here is a
recipe on how to get the installation limping along.&lt;/p&gt;

&lt;p&gt;First, download the test ISO via
&lt;a href=&quot;ftp://ftp.skolelinux.no/cd-edu-testing-nolocal-netinst/debian-edu-amd64-i386-NETINST-1.iso&quot;&gt;ftp&lt;/a&gt;,
&lt;a href=&quot;http://ftp.skolelinux.no/cd-edu-testing-nolocal-netinst/debian-edu-amd64-i386-NETINST-1.iso&quot;&gt;http&lt;/a&gt;
or rsync (use
ftp.skolelinux.org::cd-edu-testing-nolocal-netinst/debian-edu-amd64-i386-NETINST-1.iso).
The ISO build was broken on Tuesday, so we do not get a new ISO every
12 hours or so, but thankfully the ISO we already got we are able to
install with some tweaking.&lt;/p&gt;

&lt;p&gt;When you get to the Debian Edu profile question, go to tty2
(use Alt-Ctrl-F2), run&lt;/p&gt;

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
nano /usr/bin/edu-eatmydata-install
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;and add &#39;exit 0&#39; as the second line, disabling the eatmydata
optimization.  Return to the installation, select the profile you want
and continue.  Without this change, exim4-config will fail to install
due to a known bug in eatmydata.&lt;/p&gt;

&lt;p&gt;When you get the grub question at the end, answer /dev/sda (or if
this do not work, figure out what your correct value would be.  All my
test machines need /dev/sda, so I have no advice if it do not fit
your need.&lt;/p&gt;

&lt;p&gt;If you installed a profile including a graphical desktop, log in as
root after the initial boot from hard drive, and install the
education-desktop-XXX metapackage.  XXX can be kde, gnome, lxde, xfce
or mate.  If you want several desktop options, install more than one
metapackage.  Once this is done, reboot and you should have a working
graphical login screen.  This workaround should no longer be needed
once the education-tasks package version 1.801 enter testing in two
days.&lt;/p&gt;

&lt;p&gt;I believe the ISO build will start working on two days when the new
tasksel package enter testing and Steve McIntyre get a chance to
update the debian-cd git repository.  The eatmydata, grub and desktop
issues are already fixed in unstable and testing, and should show up
on the ISO as soon as the ISO build start working again.  Well the
eatmydata optimization is really just disabled.  The proper fix
require an upload by the eatmydata maintainer applying the patch
provided in bug &lt;a href=&quot;https://bugs.debian.org/702711&quot;&gt;#702711&lt;/a&gt;.
The rest have proper fixes in unstable.&lt;/p&gt;

&lt;p&gt;I hope this get you going with the installation testing, as we are
quickly running out of time trying to get our Jessie based
installation ready before the distribution freeze in a month.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Suddenly I am the new upstream of the lsdvd command line tool</title>
                <link>http://www.hungry.com/~pere/blog/Suddenly_I_am_the_new_upstream_of_the_lsdvd_command_line_tool.html</link>        
                <guid isPermaLink="true">http://www.hungry.com/~pere/blog/Suddenly_I_am_the_new_upstream_of_the_lsdvd_command_line_tool.html</guid>
                <pubDate>Thu, 25 Sep 2014 11:20:00 +0200</pubDate>
                <description>&lt;p&gt;I use the &lt;a href=&quot;https://sourceforge.net/p/lsdvd/&quot;&gt;lsdvd tool&lt;/a&gt;
to handle my fairly large DVD collection.  It is a nice command line
tool to get details about a DVD, like title, tracks, track length,
etc, in XML, Perl or human readable format.  But lsdvd have not seen
any new development since 2006 and had a few irritating bugs affecting
its use with some DVDs.  Upstream seemed to be dead, and in January I
sent a small probe asking for a version control repository for the
project, without any reply.  But I use it regularly and would like to
get &lt;a href=&quot;https://packages.qa.debian.org/lsdvd&quot;&gt;an updated version
into Debian&lt;/a&gt;.  So two weeks ago I tried harder to get in touch with
the project admin, and after getting a reply from him explaining that
he was no longer interested in the project, I asked if I could take
over.  And yesterday, I became project admin.&lt;/p&gt;

&lt;p&gt;I&#39;ve been in touch with a Gentoo developer and the Debian
maintainer interested in joining forces to maintain the upstream
project, and I hope we can get a new release out fairly quickly,
collecting the patches spread around on the internet into on place.
I&#39;ve added the relevant Debian patches to the freshly created git
repository, and expect the Gentoo patches to make it too.  If you got
a DVD collection and care about command line tools, check out
&lt;a href=&quot;https://sourceforge.net/p/lsdvd/git/ci/master/tree/&quot;&gt;the git source&lt;/a&gt; and join
&lt;a href=&quot;https://sourceforge.net/p/lsdvd/mailman/&quot;&gt;the project mailing
list&lt;/a&gt;. :)&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Hva henger under skibrua over E16 på Sollihøgda?</title>
                <link>http://www.hungry.com/~pere/blog/Hva_henger_under_skibrua_over_E16_p__Sollih_gda_.html</link>        
                <guid isPermaLink="true">http://www.hungry.com/~pere/blog/Hva_henger_under_skibrua_over_E16_p__Sollih_gda_.html</guid>
                <pubDate>Sun, 21 Sep 2014 09:50:00 +0200</pubDate>
                <description>&lt;p&gt;Rundt omkring i Oslo og Østlandsområdet henger det bokser over
veiene som jeg har lurt på hva gjør.  De har ut fra plassering og
vinkling sett ut som bokser som sniffer ut et eller annet fra
forbipasserende trafikk, men det har vært uklart for meg hva det er de
leser av.  Her om dagen tok jeg bilde av en slik boks som henger under
&lt;a href=&quot;http://www.openstreetmap.no/?zoom=19&amp;mlat=59.96396&amp;mlon=10.34443&amp;layers=B00000&quot;&gt;ei
skibru på Sollihøgda&lt;/a&gt;:&lt;/p&gt;

&lt;p align=&quot;center&quot;&gt;&lt;img width=&quot;60%&quot; src=&quot;https://people.skolelinux.org/pere/blog/images/2014-09-13-kapsch-sollihogda-crop.jpeg&quot;&gt;&lt;/p&gt;

&lt;p&gt;Boksen er tydelig merket «Kapsch &gt;&gt;&gt;», logoen til
&lt;a href=&quot;http://www.kapsch.net/&quot;&gt;det sveitsiske selskapet Kapsch&lt;/a&gt; som
blant annet lager sensorsystemer for veitrafikk.  Men de lager mye
forskjellig, og jeg kjente ikke igjen boksen på utseendet etter en
kjapp titt på produktlista til selskapet.&lt;/p&gt;

&lt;p&gt;I og med at boksen henger over veien E16, en riksvei vedlikeholdt
av Statens Vegvesen, så antok jeg at det burde være mulig å bruke
REST-API-et som gir tilgang til vegvesenets database over veier,
skilter og annet veirelatert til å finne ut hva i alle dager dette
kunne være.  De har både
&lt;a href=&quot;https://www.vegvesen.no/nvdb/api/dokumentasjon/datakatalog&quot;&gt;en
datakatalog&lt;/a&gt; og
&lt;a href=&quot;https://www.vegvesen.no/nvdb/api/dokumentasjon/sok&quot;&gt;et
søk&lt;/a&gt;, der en kan søke etter ulike typer oppføringer innen for et
gitt geografisk område.  Jeg laget et enkelt shell-script for å hente
ut antall av en gitt type innenfor området skibrua dekker, og listet
opp navnet på typene som ble funnet.  Orket ikke slå opp hvordan
URL-koding av aktuelle strenger kunne gjøres mer generisk, og brukte
en stygg sed-linje i stedet.&lt;/p&gt;

&lt;blockquote&gt;&lt;pre&gt;
#!/bin/sh
urlmap() {
    sed \
    -e &#39;s/  / /g&#39;   -e &#39;s/{/%7B/g&#39;  \
    -e &#39;s/}/%7D/g&#39;  -e &#39;s/\[/%5B/g&#39; \
    -e &#39;s/\]/%5D/g&#39; -e &#39;s/ /%20/g&#39;  \
    -e &#39;s/,/%2C/g&#39;  -e &#39;s/\&quot;/%22/g&#39; \
    -e &#39;s/:/%3A/g&#39;
}

lookup() {
    url=&quot;$1&quot;
    curl -s -H &#39;Accept: application/vnd.vegvesen.nvdb-v1+xml&#39; \
       &quot;https://www.vegvesen.no/nvdb/api$url&quot; | xmllint --format -
}

for id in $(seq 1 874) ; do
    search=&quot;{
  lokasjon: {
    bbox: \&quot;10.34425,59.96386,10.34458,59.96409\&quot;,
    srid: \&quot;WGS84\&quot;
  },
   objektTyper: [{
     id: $id, antall: 10
   }]
}&quot;

    query=/sok?kriterie=$(echo $search | urlmap)
    if lookup &quot;$query&quot; |
    grep -q &#39;&amp;lt;totaltAntallReturnert&gt;0&amp;lt;&#39;
    then
    :
    else
    echo $id
    lookup &quot;/datakatalog/objekttyper/$id&quot; |grep &#39;^  &amp;lt;navn&gt;&#39;
    fi
done

exit 0
&lt;/pre&gt;&lt;/blockquote&gt;

Aktuelt ID-område 1-874 var riktig i datakatalogen da jeg laget
scriptet.  Det vil endre seg over tid.  Skriptet listet så opp
aktuelle typer i og rundt skibrua:

&lt;blockquote&gt;&lt;pre&gt;
5
  &amp;lt;navn&gt;Rekkverk&amp;lt;/navn&gt;
14
  &amp;lt;navn&gt;Rekkverksende&amp;lt;/navn&gt;
47
  &amp;lt;navn&gt;Trafikklomme&amp;lt;/navn&gt;
49
  &amp;lt;navn&gt;Trafikkøy&amp;lt;/navn&gt;
60
  &amp;lt;navn&gt;Bru&amp;lt;/navn&gt;
79
  &amp;lt;navn&gt;Stikkrenne/Kulvert&amp;lt;/navn&gt;
80
  &amp;lt;navn&gt;Grøft, åpen&amp;lt;/navn&gt;
86
  &amp;lt;navn&gt;Belysningsstrekning&amp;lt;/navn&gt;
95
  &amp;lt;navn&gt;Skiltpunkt&amp;lt;/navn&gt;
96
  &amp;lt;navn&gt;Skiltplate&amp;lt;/navn&gt;
98
  &amp;lt;navn&gt;Referansestolpe&amp;lt;/navn&gt;
99
  &amp;lt;navn&gt;Vegoppmerking, langsgående&amp;lt;/navn&gt;
105
  &amp;lt;navn&gt;Fartsgrense&amp;lt;/navn&gt;
106
  &amp;lt;navn&gt;Vinterdriftsstrategi&amp;lt;/navn&gt;
172
  &amp;lt;navn&gt;Trafikkdeler&amp;lt;/navn&gt;
241
  &amp;lt;navn&gt;Vegdekke&amp;lt;/navn&gt;
293
  &amp;lt;navn&gt;Breddemåling&amp;lt;/navn&gt;
301
  &amp;lt;navn&gt;Kantklippareal&amp;lt;/navn&gt;
318
  &amp;lt;navn&gt;Snø-/isrydding&amp;lt;/navn&gt;
445
  &amp;lt;navn&gt;Skred&amp;lt;/navn&gt;
446
  &amp;lt;navn&gt;Dokumentasjon&amp;lt;/navn&gt;
452
  &amp;lt;navn&gt;Undergang&amp;lt;/navn&gt;
528
  &amp;lt;navn&gt;Tverrprofil&amp;lt;/navn&gt;
532
  &amp;lt;navn&gt;Vegreferanse&amp;lt;/navn&gt;
534
  &amp;lt;navn&gt;Region&amp;lt;/navn&gt;
535
  &amp;lt;navn&gt;Fylke&amp;lt;/navn&gt;
536
  &amp;lt;navn&gt;Kommune&amp;lt;/navn&gt;
538
  &amp;lt;navn&gt;Gate&amp;lt;/navn&gt;
539
  &amp;lt;navn&gt;Transportlenke&amp;lt;/navn&gt;
540
  &amp;lt;navn&gt;Trafikkmengde&amp;lt;/navn&gt;
570
  &amp;lt;navn&gt;Trafikkulykke&amp;lt;/navn&gt;
571
  &amp;lt;navn&gt;Ulykkesinvolvert enhet&amp;lt;/navn&gt;
572
  &amp;lt;navn&gt;Ulykkesinvolvert person&amp;lt;/navn&gt;
579
  &amp;lt;navn&gt;Politidistrikt&amp;lt;/navn&gt;
583
  &amp;lt;navn&gt;Vegbredde&amp;lt;/navn&gt;
591
  &amp;lt;navn&gt;Høydebegrensning&amp;lt;/navn&gt;
592
  &amp;lt;navn&gt;Nedbøyningsmåling&amp;lt;/navn&gt;
597
  &amp;lt;navn&gt;Støy-luft, Strekningsdata&amp;lt;/navn&gt;
601
  &amp;lt;navn&gt;Oppgravingsdata&amp;lt;/navn&gt;
602
  &amp;lt;navn&gt;Oppgravingslag&amp;lt;/navn&gt;
603
  &amp;lt;navn&gt;PMS-parsell&amp;lt;/navn&gt;
604
  &amp;lt;navn&gt;Vegnormalstrekning&amp;lt;/navn&gt;
605
  &amp;lt;navn&gt;Værrelatert strekning&amp;lt;/navn&gt;
616
  &amp;lt;navn&gt;Feltstrekning&amp;lt;/navn&gt;
617
  &amp;lt;navn&gt;Adressepunkt&amp;lt;/navn&gt;
626
  &amp;lt;navn&gt;Friksjonsmåleserie&amp;lt;/navn&gt;
629
  &amp;lt;navn&gt;Vegdekke, flatelapping&amp;lt;/navn&gt;
639
  &amp;lt;navn&gt;Kurvatur, horisontalelement&amp;lt;/navn&gt;
640
  &amp;lt;navn&gt;Kurvatur, vertikalelement&amp;lt;/navn&gt;
642
  &amp;lt;navn&gt;Kurvatur, vertikalpunkt&amp;lt;/navn&gt;
643
  &amp;lt;navn&gt;Statistikk, trafikkmengde&amp;lt;/navn&gt;
647
  &amp;lt;navn&gt;Statistikk, vegbredde&amp;lt;/navn&gt;
774
  &amp;lt;navn&gt;Nedbøyningsmåleserie&amp;lt;/navn&gt;
775
  &amp;lt;navn&gt;ATK, influensstrekning&amp;lt;/navn&gt;
794
  &amp;lt;navn&gt;Systemobjekt&amp;lt;/navn&gt;
810
  &amp;lt;navn&gt;Vinterdriftsklasse&amp;lt;/navn&gt;
821
  &amp;lt;navn&gt;Funksjonell vegklasse&amp;lt;/navn&gt;
825
  &amp;lt;navn&gt;Kurvatur, stigning&amp;lt;/navn&gt;
838
  &amp;lt;navn&gt;Vegbredde, beregnet&amp;lt;/navn&gt;
862
  &amp;lt;navn&gt;Reisetidsregistreringspunkt&amp;lt;/navn&gt;
871
  &amp;lt;navn&gt;Bruksklasse&amp;lt;/navn&gt;
&lt;/pre&gt;&lt;/blockquote&gt;

&lt;p&gt;Av disse ser ID 775 og 862 mest relevant ut.  ID 775 antar jeg
refererer til fotoboksen som står like ved brua, mens
«Reisetidsregistreringspunkt» kanskje kan være boksen som henger der.
Hvordan finner jeg så ut hva dette kan være for noe.  En titt på
&lt;a href=&quot;http://labs.vegdata.no/nvdb-datakatalog/862-Reisetidsregistreringspunkt/&quot;&gt;datakatalogsiden
for ID 862/Reisetidsregistreringspunkt&lt;/a&gt; viser at det er finnes 53
slike målere i Norge, og hvor de er plassert, men gir ellers få
detaljer.  Det er plassert 40 på østlandet og 13 i Trondheimsregionen.
Men siden nevner «AutoPASS», og hvis en slår opp oppføringen på
Sollihøgda nevner den «Ciber AS» som ID for eksternt system.  (Kan det
være snakk om
&lt;a href=&quot;http://www.proff.no/selskap/ciber-norge-as/oslo/internettdesign-og-programmering/Z0I3KMF4/&quot;&gt;Ciber
Norge AS&lt;/a&gt;, et selskap eid av Ciber Europe Bv?)  Et nettsøk på
 «Ciber AS autopass» fører meg til en artikkel fra NRK Trøndelag i
 2013 med tittel
«&lt;a href=&quot;http://www.nrk.no/trondelag/sjekk-dette-hvis-du-vil-unnga-ko-1.11327947&quot;&gt;Sjekk
dette hvis du vil unngå kø&lt;/a&gt;».  Artikkelen henviser til vegvesenets
nettside
&lt;a href=&quot;http://www.reisetider.no/reisetid/forside.html&quot;&gt;reisetider.no&lt;/a&gt;
som har en
&lt;a href=&quot;http://www.reisetider.no/reisetid/omrade.html?omrade=5&quot;&gt;kartside
for Østlandet&lt;/a&gt; som viser at det måles mellom Sandvika og Sollihøgda.
Det kan dermed se ut til at jeg har funnet ut hva boksene gjør.&lt;/p&gt;

&lt;p&gt;Hvis det stemmer, så er dette bokser som leser av AutoPASS-ID-en
til alle passerende biler med AutoPASS-brikke, og dermed gjør det mulig
for de som kontrollerer boksene å holde rede på hvor en gitt bil er
når den passerte et slikt målepunkt.  NRK-artikkelen forteller at
denne informasjonen i dag kun brukes til å koble to
AutoPASS-brikkepasseringer passeringer sammen for å beregne
reisetiden, og at bruken er godkjent av Datatilsynet.  Det er desverre
ikke mulig for en sjåfør som passerer under en slik boks å kontrollere
at AutoPASS-ID-en kun brukes til dette i dag og i fremtiden.&lt;/p&gt;

&lt;p&gt;I tillegg til denne type AutoPASS-sniffere vet jeg at det også
finnes mange automatiske stasjoner som tar betalt pr. passering (aka
bomstasjoner), og der lagres informasjon om tid, sted og bilnummer i
10 år.  Finnes det andre slike sniffere plassert ut på veiene?&lt;/p&gt;

&lt;p&gt;Personlig har jeg valgt å ikke bruke AutoPASS-brikke, for å gjøre
det vanskeligere og mer kostbart for de som vil invadere privatsfæren
og holde rede på hvor bilen min beveger seg til enhver tid.  Jeg håper
flere vil gjøre det samme, selv om det gir litt høyere private
utgifter (dyrere bompassering).  Vern om privatsfæren koster i disse
dager.&lt;/p&gt;

&lt;p&gt;Takk til Jan Kristian Jensen i Statens Vegvesen for tips om
dokumentasjon på vegvesenets REST-API.&lt;/p&gt;

&lt;p&gt;Bruksvilkår på bildet er
&lt;a href=&quot;https://creativecommons.org/publicdomain/&quot;&gt;public domain eller
CC0&lt;/a&gt; alt etter hva som fungerer best for mottaker.&lt;/p&gt;

&lt;p&gt;Oppdatering 2014-12-17: Veldig hyggelig å se at mine notater
&lt;a href=&quot;http://www.vegdata.no/2014/11/04/hva-henger-under-brua-over-e16-pa-sollihogda/&quot;&gt;fikk
omtale på vegdata-bloggen&lt;/a&gt;.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Speeding up the Debian installer using eatmydata and dpkg-divert</title>
                <link>http://www.hungry.com/~pere/blog/Speeding_up_the_Debian_installer_using_eatmydata_and_dpkg_divert.html</link>        
                <guid isPermaLink="true">http://www.hungry.com/~pere/blog/Speeding_up_the_Debian_installer_using_eatmydata_and_dpkg_divert.html</guid>
                <pubDate>Tue, 16 Sep 2014 14:00:00 +0200</pubDate>
                <description>&lt;p&gt;The &lt;a href=&quot;https://www.debian.org/&quot;&gt;Debian&lt;/a&gt; installer could be
a lot quicker.  When we install more than 2000 packages in
&lt;a href=&quot;http://www.skolelinux.org/&quot;&gt;Skolelinux / Debian Edu&lt;/a&gt; using
tasksel in the installer, unpacking the binary packages take forever.
A part of the slow I/O issue was discussed in
&lt;a href=&quot;https://bugs.debian.org/613428&quot;&gt;bug #613428&lt;/a&gt; about too
much file system sync-ing done by dpkg, which is the package
responsible for unpacking the binary packages.  Other parts (like code
executed by postinst scripts) might also sync to disk during
installation.  All this sync-ing to disk do not really make sense to
me.  If the machine crash half-way through, I start over, I do not try
to salvage the half installed system.  So the failure sync-ing is
supposed to protect against, hardware or system crash, is not really
relevant while the installer is running.&lt;/p&gt;

&lt;p&gt;A few days ago, I thought of a way to get rid of all the file
system sync()-ing in a fairly non-intrusive way, without the need to
change the code in several packages.  The idea is not new, but I have
not heard anyone propose the approach using dpkg-divert before.  It
depend on the small and clever package
&lt;a href=&quot;https://packages.qa.debian.org/eatmydata&quot;&gt;eatmydata&lt;/a&gt;, which
uses LD_PRELOAD to replace the system functions for syncing data to
disk with functions doing nothing, thus allowing programs to live
dangerous while speeding up disk I/O significantly.  Instead of
modifying the implementation of dpkg, apt and tasksel (which are the
packages responsible for selecting, fetching and installing packages),
it occurred to me that we could just divert the programs away, replace
them with a simple shell wrapper calling
&quot;eatmydata&amp;nbsp;$program&amp;nbsp;$@&quot;, to get the same effect.
Two days ago I decided to test the idea, and wrapped up a simple
implementation for the Debian Edu udeb.&lt;/p&gt;

&lt;p&gt;The effect was stunning.  In my first test it reduced the running
time of the pkgsel step (installing tasks) from 64 to less than 44
minutes (20 minutes shaved off the installation) on an old Dell
Latitude D505 machine.  I am not quite sure what the optimised time
would have been, as I messed up the testing a bit, causing the debconf
priority to get low enough for two questions to pop up during
installation.  As soon as I saw the questions I moved the installation
along, but do not know how long the question were holding up the
installation.  I did some more measurements using Debian Edu Jessie,
and got these results.  The time measured is the time stamp in
/var/log/syslog between the &quot;pkgsel: starting tasksel&quot; and the
&quot;pkgsel: finishing up&quot; lines, if you want to do the same measurement
yourself.  In Debian Edu, the tasksel dialog do not show up, and the
timing thus do not depend on how quickly the user handle the tasksel
dialog.&lt;/p&gt;

&lt;p&gt;&lt;table&gt;

&lt;tr&gt;
&lt;th&gt;Machine/setup&lt;/th&gt;
&lt;th&gt;Original tasksel&lt;/th&gt;
&lt;th&gt;Optimised tasksel&lt;/th&gt;
&lt;th&gt;Reduction&lt;/th&gt;
&lt;/tr&gt;

&lt;tr&gt;
&lt;td&gt;Latitude D505 Main+LTSP LXDE&lt;/td&gt;
&lt;td&gt;64 min (07:46-08:50)&lt;/td&gt;
&lt;td&gt;&lt;44 min (11:27-12:11)&lt;/td&gt;
&lt;td&gt;&gt;20 min 18%&lt;/td&gt;
&lt;/tr&gt;

&lt;tr&gt;
&lt;td&gt;Latitude D505 Roaming LXDE&lt;/td&gt;
&lt;td&gt;57 min (08:48-09:45)&lt;/td&gt;
&lt;td&gt;34 min (07:43-08:17)&lt;/td&gt;
&lt;td&gt;23 min 40%&lt;/td&gt;
&lt;/tr&gt;

&lt;tr&gt;
&lt;td&gt;Latitude D505 Minimal&lt;/td&gt;
&lt;td&gt;22 min (10:37-10:59)&lt;/td&gt;
&lt;td&gt;11 min (11:16-11:27)&lt;/td&gt;
&lt;td&gt;11 min 50%&lt;/td&gt;
&lt;/tr&gt;

&lt;tr&gt;
&lt;td&gt;Thinkpad X200 Minimal&lt;/td&gt;
&lt;td&gt;6 min (08:19-08:25)&lt;/td&gt;
&lt;td&gt;4 min (08:04-08:08)&lt;/td&gt;
&lt;td&gt;2 min 33%&lt;/td&gt;
&lt;/tr&gt;

&lt;tr&gt;
&lt;td&gt;Thinkpad X200 Roaming KDE&lt;/td&gt;
&lt;td&gt;19 min (09:21-09:40)&lt;/td&gt;
&lt;td&gt;15 min (10:25-10:40)&lt;/td&gt;
&lt;td&gt;4 min 21%&lt;/td&gt;
&lt;/tr&gt;

&lt;/table&gt;&lt;/p&gt;

&lt;p&gt;The test is done using a netinst ISO on a USB stick, so some of the
time is spent downloading packages.  The connection to the Internet
was 100Mbit/s during testing, so downloading should not be a
significant factor in the measurement.  Download typically took a few
seconds to a few minutes, depending on the amount of packages being
installed.&lt;/p&gt;

&lt;p&gt;The speedup is implemented by using two hooks in
&lt;a href=&quot;https://www.debian.org/devel/debian-installer/&quot;&gt;Debian
Installer&lt;/a&gt;, the pre-pkgsel.d hook to set up the diverts, and the
finish-install.d hook to remove the divert at the end of the
installation.  I picked the pre-pkgsel.d hook instead of the
post-base-installer.d hook because I test using an ISO without the
eatmydata package included, and the post-base-installer.d hook in
Debian Edu can only operate on packages included in the ISO.  The
negative effect of this is that I am unable to activate this
optimization for the kernel installation step in d-i.  If the code is
moved to the post-base-installer.d hook, the speedup would be larger
for the entire installation.&lt;/p&gt;

&lt;p&gt;I&#39;ve implemented this in the
&lt;a href=&quot;https://packages.qa.debian.org/debian-edu-install&quot;&gt;debian-edu-install&lt;/a&gt;
git repository, and plan to provide the optimization as part of the
Debian Edu installation.  If you want to test this yourself, you can
create two files in the installer (or in an udeb).  One shell script
need do go into /usr/lib/pre-pkgsel.d/, with content like this:&lt;/p&gt;

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
#!/bin/sh
set -e
. /usr/share/debconf/confmodule
info() {
    logger -t my-pkgsel &quot;info: $*&quot;
}
error() {
    logger -t my-pkgsel &quot;error: $*&quot;
}
override_install() {
    apt-install eatmydata || true
    if [ -x /target/usr/bin/eatmydata ] ; then
        for bin in dpkg apt-get aptitude tasksel ; do
            file=/usr/bin/$bin
            # Test that the file exist and have not been diverted already.
            if [ -f /target$file ] ; then
                info &quot;diverting $file using eatmydata&quot;
                printf &quot;#!/bin/sh\neatmydata $bin.distrib \&quot;\$@\&quot;\n&quot; \
                    &gt; /target$file.edu
                chmod 755 /target$file.edu
                in-target dpkg-divert --package debian-edu-config \
                    --rename --quiet --add $file
                ln -sf ./$bin.edu /target$file
            else
                error &quot;unable to divert $file, as it is missing.&quot;
            fi
        done
    else
        error &quot;unable to find /usr/bin/eatmydata after installing the eatmydata pacage&quot;
    fi
}

override_install
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;To clean up, another shell script should go into
/usr/lib/finish-install.d/ with code like this:

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
#! /bin/sh -e
. /usr/share/debconf/confmodule
error() {
    logger -t my-finish-install &quot;error: $@&quot;
}
remove_install_override() {
    for bin in dpkg apt-get aptitude tasksel ; do
        file=/usr/bin/$bin
        if [ -x /target$file.edu ] ; then
            rm /target$file
            in-target dpkg-divert --package debian-edu-config \
                --rename --quiet --remove $file
            rm /target$file.edu
        else
            error &quot;Missing divert for $file.&quot;
        fi
    done
    sync # Flush file buffers before continuing
}

remove_install_override
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;In Debian Edu, I placed both code fragments in a separate script
edu-eatmydata-install and call it from the pre-pkgsel.d and
finish-install.d scripts.&lt;/p&gt;

&lt;p&gt;By now you might ask if this change should get into the normal
Debian installer too?  I suspect it should, but am not sure the
current debian-installer coordinators find it useful enough.  It also
depend on the side effects of the change.  I&#39;m not aware of any, but I
guess we will see if the change is safe after some more testing.
Perhaps there is some package in Debian depending on sync() and
fsync() having effect?  Perhaps it should go into its own udeb, to
allow those of us wanting to enable it to do so without affecting
everyone.&lt;/p&gt;

&lt;p&gt;Update 2014-09-24: Since a few days ago, enabling this optimization
will break installation of all programs using gnutls because of
&lt;a href=&quot;https://bugs.debian.org/702711&quot;&gt;bug #702711&lt;/a&gt;.  An updated
eatmydata package in Debian will solve it.&lt;/p&gt;

&lt;p&gt;Update 2014-10-17: The bug mentioned above is fixed in testing and
the optimization work again.  And I have discovered that the
dpkg-divert trick is not really needed and implemented a slightly
simpler approach as part of the debian-edu-install package.  See
tools/edu-eatmydata-install in the source package.&lt;/p&gt;

&lt;p&gt;Update 2014-11-11: Unfortunately, a new
&lt;a href=&quot;http://bugs.debian.org/765738&quot;&gt;bug #765738&lt;/a&gt; in eatmydata only
triggering on i386 made it into testing, and broke this installation
optimization again.  If &lt;a href=&quot;http://bugs.debian.org/768893&quot;&gt;unblock
request 768893&lt;/a&gt; is accepted, it should be working again.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Good bye subkeys.pgp.net, welcome pool.sks-keyservers.net</title>
                <link>http://www.hungry.com/~pere/blog/Good_bye_subkeys_pgp_net__welcome_pool_sks_keyservers_net.html</link>        
                <guid isPermaLink="true">http://www.hungry.com/~pere/blog/Good_bye_subkeys_pgp_net__welcome_pool_sks_keyservers_net.html</guid>
                <pubDate>Wed, 10 Sep 2014 13:10:00 +0200</pubDate>
                <description>&lt;p&gt;Yesterday, I had the pleasure of attending a talk with the
&lt;a href=&quot;http://www.nuug.no/&quot;&gt;Norwegian Unix User Group&lt;/a&gt; about
&lt;a href=&quot;http://www.nuug.no/aktiviteter/20140909-sks-keyservers/&quot;&gt;the
OpenPGP keyserver pool sks-keyservers.net&lt;/a&gt;, and was very happy to
learn that there is a large set of publicly available key servers to
use when looking for peoples public key.  So far I have used
subkeys.pgp.net, and some times wwwkeys.nl.pgp.net when the former
were misbehaving, but those days are ended.  The servers I have used
up until yesterday have been slow and some times unavailable.  I hope
those problems are gone now.&lt;/p&gt;

&lt;p&gt;Behind the round robin DNS entry of the
&lt;a href=&quot;https://sks-keyservers.net/&quot;&gt;sks-keyservers.net&lt;/a&gt; service
there is a pool of more than 100 keyservers which are checked every
day to ensure they are well connected and up to date.  It must be
better than what I have used so far. :)&lt;/p&gt;

&lt;p&gt;Yesterdays speaker told me that the service is the default
keyserver provided by the default configuration in GnuPG, but this do
not seem to be used in Debian.  Perhaps it should?&lt;/p&gt;

&lt;p&gt;Anyway, I&#39;ve updated my ~/.gnupg/options file to now include this
line:&lt;/p&gt;

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
keyserver pool.sks-keyservers.net
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;With GnuPG version 2 one can also locate the keyserver using SRV
entries in DNS.  Just for fun, I did just that at work, so now every
user of GnuPG at the University of Oslo should find a OpenGPG
keyserver automatically should their need it:&lt;/p&gt;

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
% host -t srv _pgpkey-http._tcp.uio.no
_pgpkey-http._tcp.uio.no has SRV record 0 100 11371 pool.sks-keyservers.net.
%
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;Now if only
&lt;a href=&quot;http://ietfreport.isoc.org/idref/draft-shaw-openpgp-hkp/&quot;&gt;the
HKP lookup protocol&lt;/a&gt; supported finding signature paths, I would be
very happy.  It can look up a given key or search for a user ID, but I
normally do not want that, but to find a trust path from my key to
another key.  Given a user ID or key ID, I would like to find (and
download) the keys representing a signature path from my key to the
key in question, to be able to get a trust path between the two keys.
This is as far as I can tell not possible today.  Perhaps something
for a future version of the protocol?&lt;/p&gt;
</description>
        </item>
        
        </channel>
</rss>