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                <title>Petter Reinholdtsen - Entries tagged english</title>
                <description>Entries tagged english</description>
                <link>../../</link>

        
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                <title>The sorry state of multimedia browser plugins in Debian</title>
                <link>../../The_sorry_state_of_multimedia_browser_plugins_in_Debian.html</link>        
                <guid isPermaLink="true">../../The_sorry_state_of_multimedia_browser_plugins_in_Debian.html</guid>
                <pubDate>Tue, 25 Nov 2008 00:10:00 +0100</pubDate>
                <description>
&lt;p&gt;Recently I have spent some time evaluating the multimedia browser
plugins available in Debian Lenny, to see which one we should use by
default in Debian Edu.  We need an embedded video playing plugin with
control buttons to pause or stop the video, and capable of streaming
all the multimedia content available on the web.  The test results and
notes are available on
&lt;a href=&quot;http://wiki.debian.org/DebianEdu/BrowserMultimedia&quot;&gt;the
Debian wiki&lt;/a&gt;.  I was surprised how few of the plugins are able to
fill this need.  My personal video player favorite, VLC, has a really
bad plugin which fail on a lot of the test pages.  A lot of the MIME
types I would expect to work with any free software player (like
video/ogg), just do not work.  And simple formats like the
audio/x-mplegurl format (m3u playlists), just isn&#39;t supported by the
totem and vlc plugins.  I hope the situation will improve soon.  No
wonder sites use the proprietary Adobe flash to play video.&lt;/p&gt;

&lt;p&gt;For Lenny, we seem to end up with the mplayer plugin.  It seem to
be the only one fitting our needs. :/&lt;/p&gt;
</description>
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                <title>Devcamp brought us closer to the Lenny based Debian Edu release</title>
                <link>../../Devcamp_brought_us_closer_to_the_Lenny_based_Debian_Edu_release.html</link>        
                <guid isPermaLink="true">../../Devcamp_brought_us_closer_to_the_Lenny_based_Debian_Edu_release.html</guid>
                <pubDate>Sun, 7 Dec 2008 12:00:00 +0100</pubDate>
                <description>
&lt;p&gt;This weekend we had a small developer gathering for Debian Edu in
Oslo.  Most of Saturday was used for the general assemly for the
member organization, but the rest of the weekend I used to tune the
LTSP installation.  LTSP now work out of the box on the 10-network.
Acer Aspire One proved to be a very nice thin client, with both
screen, mouse and keybard in a small box.  Was working on getting the
diskless workstation setup configured out of the box, but did not
finish it before the weekend was up.&lt;/p&gt;

&lt;p&gt;Did not find time to look at the 4 VGA cards in one box we got from
the Brazilian group, so that will have to wait for the next
development gathering.  Would love to have the Debian Edu installer
automatically detect and configure a multiseat setup when it find one
of these cards.&lt;/p&gt;
</description>
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                <title>Software video mixer on a USB stick</title>
                <link>../../Software_video_mixer_on_a_USB_stick.html</link>        
                <guid isPermaLink="true">../../Software_video_mixer_on_a_USB_stick.html</guid>
                <pubDate>Sun, 28 Dec 2008 15:40:00 +0100</pubDate>
                <description>
&lt;p&gt;The &lt;a href=&quot;http://www.nuug.no/&quot;&gt;Norwegian Unix User Group&lt;/a&gt; is
recording our montly presentation on video, and recently we have
worked on improving the quality of the recordings by mixing the slides
directly with the video stream.  For this, we use the
&lt;a href=&quot;http://dvswitch.alioth.debian.org/&quot;&gt;dvswitch&lt;/a&gt; package from
the Debian video team.  As this require quite one computer per video
source, and NUUG do not have enough laptops available, we need to
borrow laptops.  And to avoid having to install extra software on
these borrwed laptops, I have wrapped up all the programs needed on a
bootable USB stick.  The software required is dvswitch with assosiated
source, sink and mixer applications and
&lt;a href=&quot;http://www.kinodv.org/&quot;&gt;dvgrab&lt;/a&gt;.  To allow this setup to
work without any configuration, I&#39;ve patched dvswitch to use
&lt;a href=&quot;http://www.avahi.org/&quot;&gt;avahi&lt;/a&gt; to connect the various parts
together.  And to allow us to use laptops without firewire plugs, I
upgraded dvgrab to the one from Debian/unstable to get one that work
with USB sources.  We have not yet tested this setup in a production
setup, but I hope it will work properly, and allow us to set up a
video mixer in a very short time frame.  We will need it for
&lt;a href=&quot;http://www.goopen.no/&quot;&gt;Go Open 2009&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;&lt;a href=&quot;http://www.nuug.no/pub/video/bin/usbstick-dvswitch.img.gz&quot;&gt;The
USB image&lt;/a&gt; is for a 1 GB memory stick, but can be used on any
larger stick as well.&lt;/p&gt;
</description>
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                <title>When web browser developers make a video player...</title>
                <link>../../When_web_browser_developers_make_a_video_player___.html</link>        
                <guid isPermaLink="true">../../When_web_browser_developers_make_a_video_player___.html</guid>
                <pubDate>Sat, 17 Jan 2009 18:50:00 +0100</pubDate>
                <description>
&lt;p&gt;As part of the work we do in &lt;a href=&quot;http://www.nuug.no&quot;&gt;NUUG&lt;/a&gt;
to publish video recordings of our monthly presentations, we provide a
page with embedded video for easy access to the recording.  Putting a
good set of HTML tags together to get working embedded video in all
browsers and across all operating systems is not easy.  I hope this
will become easier when the &amp;lt;video&amp;gt; tag is implemented in all
browsers, but I am not sure.  We provide the recordings in several
formats, MPEG1, Ogg Theora, H.264 and Quicktime, and want the
browser/media plugin to pick one it support and use it to play the
recording, using whatever embed mechanism the browser understand.
There is at least four different tags to use for this, the new HTML5
&amp;lt;video&amp;gt; tag, the &amp;lt;object&amp;gt; tag, the &amp;lt;embed&amp;gt; tag and
the &amp;lt;applet&amp;gt; tag.  All of these take a lot of options, and
finding the best options is a major challenge.&lt;/p&gt;

&lt;p&gt;I just tested the experimental Opera browser available from &lt;a
href=&quot;http://labs.opera.com&quot;&gt;labs.opera.com&lt;/a&gt;, to see how it handled
a &amp;lt;video&amp;gt; tag with a few video sources and no extra attributes.
I was not very impressed.  The browser start by fetching a picture
from the video stream.  Not sure if it is the first frame, but it is
definitely very early in the recording.  So far, so good. Next,
instead of streaming the 76 MiB video file, it start to download all
of it, but do not start to play the video.  This mean I have to wait
for several minutes for the downloading to finish.  When the download
is done, the playing of the video do not start!  Waiting for the
download, but I do not get to see the video?  Some testing later, I
discover that I have to add the controls=&quot;true&quot; attribute to be able
to get a play button to pres to start the video.  Adding
autoplay=&quot;true&quot; did not help.  I sure hope this is a misfeature of the
test version of Opera, and that future implementations of the
&amp;lt;video&amp;gt; tag will stream recordings by default, or at least start
playing when the download is done.&lt;/p&gt;

&lt;p&gt;The test page I used (since changed to add more attributes) is
&lt;a href=&quot;http://www.nuug.no/aktiviteter/20090113-foredrag-om-foredrag/&quot;&gt;available
from the nuug site&lt;/a&gt;.  Will have to test it with the new Firefox
too.&lt;/p&gt;

&lt;p&gt;In the test process, I discovered a missing feature.  I was unable
to find a way to get the URL of the playing video out of Opera, so I
am not quite sure it picked the Ogg Theora version of the video.  I
sure hope it was using the announced Ogg Theora support. :)&lt;/p&gt;
</description>
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                <title>Using bar codes at a computing center</title>
                <link>../../Using_bar_codes_at_a_computing_center.html</link>        
                <guid isPermaLink="true">../../Using_bar_codes_at_a_computing_center.html</guid>
                <pubDate>Fri, 20 Feb 2009 08:50:00 +0100</pubDate>
                <description>
&lt;p&gt;At work with the University of Oslo, we have several hundred computers
in our computing center.  This give us a challenge in tracking the
location and cabling of the computers, when they are added, moved and
removed.  Some times the location register is not updated when a
computer is inserted or moved and we then have to search the room for
the &quot;missing&quot; computer.&lt;/p&gt;

&lt;p&gt;In the last issue of Linux Journal, I came across a project
&lt;a href=&quot;http://www.libdmtx.org/&quot;&gt;libdmtx&lt;/a&gt; to write and read bar
code blocks as defined in the
&lt;a href=&quot;http://en.wikipedia.org/wiki/Data_Matrix&quot;&gt;The Data Matrix
Standard&lt;/a&gt;.  This is bar codes that can be read with a normal
digital camera, for example that on a cell phone, and several such bar
codes can be read by libdmtx from one picture.  The bar code standard
allow up to 2 KiB to be written in the tag.  There is another project
with &lt;a href=&quot;http://www.terryburton.co.uk/barcodewriter/&quot;&gt;a bar code
writer written in postscript&lt;/a&gt; capable of creating such bar codes,
but this was the first time I found a tool to read these bar
codes.&lt;/p&gt;

&lt;p&gt;It occurred to me that this could be used to tag and track the
machines in our computing center.  If both racks and computers are
tagged this way, we can use a picture of the rack and all its
computers to detect the rack location of any computer in that rack.
If we do this regularly for the entire room, we will find all
locations, and can detect movements and removals.&lt;/p&gt;

&lt;p&gt;I decided to test if this would work in practice, and picked a
random rack and tagged all the machines with their names.  Next, I
took pictures with my digital camera, and gave the dmtxread program
these JPEG pictures to see how many tags it could read.  This worked
fairly well.  If the pictures was well focused and not taken from the
side, all tags in the image could be read.  Because of limited space
between the racks, I was unable to get a good picture of the entire
rack, but could without problem read all tags from a picture covering
about half the rack.  I had to limit the search time used by dmtxread
to 60000 ms to make sure it terminated in a reasonable time frame.&lt;/p&gt;

&lt;p&gt;My conclusion is that this could work, and we should probably look
at adjusting our computer tagging procedures to use bar codes for
easier automatic tracking of computers.&lt;/p&gt;
</description>
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                <title>Checking server hardware support status for Dell, HP and IBM servers</title>
                <link>../../Checking_server_hardware_support_status_for_Dell__HP_and_IBM_servers.html</link>        
                <guid isPermaLink="true">../../Checking_server_hardware_support_status_for_Dell__HP_and_IBM_servers.html</guid>
                <pubDate>Sat, 28 Feb 2009 23:50:00 +0100</pubDate>
                <description>
&lt;p&gt;At work, we have a few hundred Linux servers, and with that amount
of hardware it is important to keep track of when the hardware support
contract expire for each server.  We have a machine (and service)
register, which until recently did not contain much useful besides the
machine room location and contact information for the system owner for
each machine.  To make it easier for us to track support contract
status, I&#39;ve recently spent time on extending the machine register to
include information about when the support contract expire, and to tag
machines with expired contracts to make it easy to get a list of such
machines.  I extended a perl script already being used to import
information about machines into the register, to also do some screen
scraping off the sites of Dell, HP and IBM (our majority of machines
are from these vendors), and automatically check the support status
for the relevant machines.  This make the support status information
easily available and I hope it will make it easier for the computer
owner to know when to get new hardware or renew the support contract.
The result of this work documented that 27% of the machines in the
registry is without a support contract, and made it very easy to find
them.  27% might seem like a lot, but I see it more as the case of us
using machines a bit longer than the 3 years a normal support contract
last, to have test machines and a platform for less important
services.  After all, the machines without a contract are working fine
at the moment and the lack of contract is only a problem if any of
them break down.  When that happen, we can either fix it using spare
parts from other machines or move the service to another old
machine.&lt;/p&gt;

&lt;p&gt;I believe the code for screen scraping the Dell site was originally
written by Trond Hasle Amundsen, and later adjusted by me and Morten
Werner Forsbring.  The HP scraping was written by me after reading a
nice article in ;login: about how to use WWW::Mechanize, and the IBM
scraping was written by me based on the Dell code.  I know the HTML
parsing could be done using nice libraries, but did not want to
introduce more dependencies.  This is the current incarnation:&lt;/p&gt;

&lt;pre&gt;
use LWP::Simple;
use POSIX;
use WWW::Mechanize;
use Date::Parse;
[...]
sub get_support_info {
    my ($machine, $model, $serial, $productnumber) = @_;
    my $str;

    if ( $model =~ m/^Dell / ) {
        # fetch website from Dell support
        my $url = &quot;http://support.euro.dell.com/support/topics/topic.aspx/emea/shared/support/my_systems_info/no/details?c=no&amp;amp;cs=nodhs1&amp;amp;l=no&amp;amp;s=dhs&amp;amp;ServiceTag=$serial&quot;;
        my $webpage = get($url);
        return undef unless ($webpage);

        my $daysleft = -1;
        my @lines = split(/\n/, $webpage);
        foreach my $line (@lines) {
            next unless ($line =~ m/Beskrivelse/);
            $line =~ s/&amp;lt;[^&gt;]+?&gt;/;/gm;
            $line =~ s/^.+?;(Beskrivelse;)/$1/;

            my @f = split(/\;/, $line);
            @f = @f[13 .. $#f];
            my $lastend = &quot;&quot;;
            while ($f[3] eq &quot;DELL&quot;) {
                my ($type, $startstr, $endstr, $days) = @f[0, 5, 7, 10];

                my $start = POSIX::strftime(&quot;%Y-%m-%d&quot;,
                                            localtime(str2time($startstr)));
                my $end = POSIX::strftime(&quot;%Y-%m-%d&quot;,
                                          localtime(str2time($endstr)));
                $str .= &quot;$type $start -&gt; $end &quot;;
                @f = @f[14 .. $#f];
                $lastend = $end if ($end gt $lastend);
            }
            my $today = POSIX::strftime(&quot;%Y-%m-%d&quot;, localtime(time));
            tag_machine_unsupported($machine)
                if ($lastend lt $today);
        }
    } elsif ( $model =~ m/^HP / ) {
        my $mech = WWW::Mechanize-&gt;new();
        my $url =
            &#39;http://www1.itrc.hp.com/service/ewarranty/warrantyInput.do&#39;;
        $mech-&gt;get($url);
        my $fields = {
            &#39;BODServiceID&#39; =&gt; &#39;NA&#39;,
            &#39;RegisteredPurchaseDate&#39; =&gt; &#39;&#39;,
            &#39;country&#39; =&gt; &#39;NO&#39;,
            &#39;productNumber&#39; =&gt; $productnumber,
            &#39;serialNumber1&#39; =&gt; $serial,
        };
        $mech-&gt;submit_form( form_number =&gt; 2,
                            fields      =&gt; $fields );
        # Next step is screen scraping
        my $content = $mech-&gt;content();

        $content =~ s/&amp;lt;[^&gt;]+?&gt;/;/gm;
        $content =~ s/\s+/ /gm;
        $content =~ s/;\s*;/;;/gm;
        $content =~ s/;[\s;]+/;/gm;

        my $today = POSIX::strftime(&quot;%Y-%m-%d&quot;, localtime(time));

        while ($content =~ m/;Warranty Type;/) {
            my ($type, $status, $startstr, $stopstr) = $content =~
                m/;Warranty Type;([^;]+);.+?;Status;(\w+);Start Date;([^;]+);End Date;([^;]+);/;
            $content =~ s/^.+?;Warranty Type;//;
            my $start = POSIX::strftime(&quot;%Y-%m-%d&quot;,
                                        localtime(str2time($startstr)));
            my $end = POSIX::strftime(&quot;%Y-%m-%d&quot;,
                                      localtime(str2time($stopstr)));

            $str .= &quot;$type ($status) $start -&gt; $end &quot;;

            tag_machine_unsupported($machine)
                if ($end lt $today);
        }
    } elsif ( $model =~ m/^IBM / ) {
        # This code ignore extended support contracts.
        my ($producttype) = $model =~ m/.*-\[(.{4}).+\]-/;
        if ($producttype &amp;amp;&amp;amp; $serial) {
            my $content =
                get(&quot;http://www-947.ibm.com/systems/support/supportsite.wss/warranty?action=warranty&amp;amp;brandind=5000008&amp;amp;Submit=Submit&amp;amp;type=$producttype&amp;amp;serial=$serial&quot;);
            if ($content) {
                $content =~ s/&amp;lt;[^&gt;]+?&gt;/;/gm;
                $content =~ s/\s+/ /gm;
                $content =~ s/;\s*;/;;/gm;
                $content =~ s/;[\s;]+/;/gm;

                $content =~ s/^.+?;Warranty status;//;
                my ($status, $end) = $content =~ m/;Warranty status;([^;]+)\s*;Expiration date;(\S+) ;/;

                $str .= &quot;($status) -&gt; $end &quot;;

                my $today = POSIX::strftime(&quot;%Y-%m-%d&quot;, localtime(time));
                tag_machine_unsupported($machine)
                    if ($end lt $today);
            }
        }
    }
    return $str;
}
&lt;/pre&gt;

&lt;p&gt;Here are some examples on how to use the function, using fake
serial numbers.  The information passed in as arguments are fetched
from dmidecode.&lt;/p&gt;

&lt;pre&gt;
print get_support_info(&quot;hp.host&quot;, &quot;HP ProLiant BL460c G1&quot;, &quot;1234567890&quot;
                       &quot;447707-B21&quot;);
print get_support_info(&quot;dell.host&quot;, &quot;Dell Inc. PowerEdge 2950&quot;, &quot;1234567&quot;);
print get_support_info(&quot;ibm.host&quot;, &quot;IBM eserver xSeries 345 -[867061X]-&quot;,
                       &quot;1234567&quot;);
&lt;/pre&gt;

&lt;p&gt;I would recommend this approach for tracking support contracts for
everyone with more than a few computers to administer. :)&lt;/p&gt;

&lt;p&gt;Update 2009-03-06: The IBM page do not include extended support
contracts, so it is useless in that case.  The original Dell code do
not handle extended support contracts either, but has been updated to
do so.&lt;/p&gt;
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