Archive for the ‘System engineering’ Category
Solved: Xserver lock-ups in Ubuntu 10.04 with intel GFX
Wednesday, June 23rd, 2010
Posted in: intel, lucid, Xserver System engineering, open source, ubuntu.
After installing 10.04 I experienced a GDM lockup a couple of times a day – the symptoms varied from the window management not reacting to left mouse clicks to a complete freeze of the Xserver. This bug has caused a lot of noise across distributions, for instance in 590109 and 538563. The symptoms are log messages such as
[mi] EQ overflowing. The server is probably stuck in an infinite loop.
...
Backtrace:
...
... /usr/lib/xorg/modules/drivers/intel_drv.so
...
in the :0… logfiles in /var/log/gdm when the problem occurs.
This is, however, not a kernel, XServer or GDM issue, but caused by a problem with the intel-linux driver. The problem is apparently fixed as of version 2:2.11.0-1ubuntu1 of the xserver-xorg-video-intel driver. Since this is not (yet) an update in the official distribution repo, I did the following to solve the issue:
1: Optional: Update to the latest stable kernel
Reason: IMO, upstream Intel drivers are usually build against the latest stable kernel
Goto http://kernel.ubuntu.com/~kernel-ppa/mainline/v2.6.34-lucid/ and download the headers… _all.deb, headers-generic …..deb and linux-image… .deb for your platform (in most cases, i368). install the generic headers package, then the all headers package, then the image.
A word of warning: If you install this custom kernel you will not receive security updates for it from the automatic distribution updates.
2: Add the X Updates PPA to your sources.list
In a terminal, type:
sudo gedit /etc/apt/sources.list
And add at the bottom of the file (if not already present):
deb http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu lucid main #X-Updates PPA
deb-src http://ppa.launchpad.net/ubuntu-x-swat/x-updates/ubuntu lucid main #X-Updates PPA
2.1: Trust the software packages from the x-updates PPA
sudo apt-key adv –recv-keys –keyserver keyserver.ubuntu.com AF1CDFA9
3: Update the driver
sudo apt-get update
sudo apt-get dist-upgrade
Reboot – the problem should be solved.
No CommentsRunning mvn:release with Subversion 1.5.x
Monday, March 23rd, 2009
Posted in: J2EE, SCM, System engineering, java, maven 2, open source, subversion.
When attempting to prepare a release using maven and the maven-release-plugin, you are currently very likely to see your build fail with a message such as:
[INFO] Executing: svn --non-interactive copy --file /tmp/...commit . https://subversion..../tags/...
[INFO] Working directory: ...
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Unable to tag SCM
Provider message:
The svn tag command failed.
Command output:
svn: Commit failed (details follow):
svn: File '...' already exists
If you do, you are using subversion 1.5.x which no longer supports tagging from a local working copy, thus causing the unfortunately very misleading error message.
This is a known issue of the subversion sourcecode management (SCM) and there is a simple workaround:
Read the rest of “Running mvn:release with Subversion 1.5.x”
Debian etch and “The following packages have been kept back…”
Sunday, February 15th, 2009
Posted in: System engineering, debian 4, lenny, open source.
Just for the record: It seems the new Debian Lenny release is close at hand.
Apparently a few packages for the lenny release already made it into the productive repositories, which causes them to be held back by apt-get upgrade:
apt-get dist-upgrade -V
Reading package lists... Done
Building dependency tree... Done
Calculating upgrade... Done
The following packages have been kept back:
libapache2-mod-php5 (... => 5.2.6.dfsg.1-1+lenny2)
libperl5.8 (... => 5.8.8-11.1+lenny1)
php-pear (... => 5.2.6.dfsg.1-1+lenny2)
...
apt-get dist-upgrade, which usually resolves this issue by upgrading the system to the most recent release does not work yet, since lenny was not released so far.
No CommentsCreating a PPTP VPN connection in Ubuntu 8.10 (Intrepid)
Tuesday, November 4th, 2008
Posted in: System engineering, intrepid, ubuntu.
Update June 22, 2010
The configuration described below is still valid up to the most recent Ubuntu release (10.04) !
Update December 8, 2008
The following solution does not work for everybody as there are multiple issues with VPN connections, the network manager etc. Bug fixing is in progress and it appears a number of patches where already included in recent ubuntu updates.
I recommend checking the ubuntu bug database for the latest state of the VPN issues:
This monday was sweet. I finally had the time to make a fresh install of ubuntu 8.10 on my thinkpad r52, and what can i say, just as all the other releases before, things got better.
I am especially happy about the re-programmed network manager, which works a whole lot better than in hardy.
Except that i didn’t get the PPTP VPN connection to my office to work instantly.
Read the rest of “Creating a PPTP VPN connection in Ubuntu 8.10 (Intrepid)”
Configuring Eclipse Ganymede with subversion in Ubuntu 8.04
Sunday, July 13th, 2008
Posted in: J2EE, SCM, System engineering, eclipse, java, subclipse, subversion, subversive, ubuntu.
After installing the all-new Eclipse ganymede (by downloading it from the eclipse site) under ubuntu 8.04 i ran into some trouble after installing version 1.4.1 of the subclipse subversion plugin.
Long story short, subclipse requires subversion 1.5, but ubuntu 8.04 provides 1.4.x.
If you still want to use subclipse with ganymede in ubuntu, there are only two ways two achieve this – both of which i cannot recommend because they are hacks or bad compromises.
Read the rest of “Configuring Eclipse Ganymede with subversion in Ubuntu 8.04″
Critical security vulnerability in debian openssl package
Wednesday, May 14th, 2008
Posted in: System engineering, debian 4, ubuntu.
Debians security advisory has reported a critical security issue with debian-based openssl packages.
As a result,generated keys might be weak and breakable, since the random number generator appears to have created predictable results.
The exact nature of this predictability was not made public by now, but it is strongly recommendet to regenerate keys created with kryptographic tools affected by the issue and to re-enroll all corresponding certificates.
Note that his issue affects all debian-based systems, including ubuntu 8.04.
Source: http://lists.debian.org/debian-security-announce/2008/msg00152.html
Seems i’ll have a somewhat busy weekend.
No CommentsConfiguring custom username for maven’s scm with subversion and ssh
Monday, April 21st, 2008
Posted in: System engineering, continuum, java, maven 2, subversion.
I just stumbled over a nice little problem: When using the maven 2 changelog plugin, it automatically uses the configured <scm> settings and attempts to fetch the change history with them.
Unfortunately, such a setting usually does not contain a username, since this has to be provided by the actual team member connecting to version control.
Neither did i have any intention to configure a placeholder into the scm section, forcing the developers to mess with the maven settings.xml in order to provide their own username.
Luckily, after searching a while, i found a proper solution.
SSH allows an optional per-host specific username setting to be placed in a file called “config” located in the user’s .ssh directory, for example
File: ~/.ssh/config
Host my.host.name
User myusername
Thanks to Chad Humphries for posting the Solution on programming is hard.
It really wasn’t…
maven autocompletion für die shell (und windows)
Wednesday, March 26th, 2008
Posted in: System engineering, java, maven 2, ubuntu.
Beim Arbeiten mit maven stört die fehlende automatische Vervollständigung auf der Kommadozeile, insbesondere wenn man den Komfort einer ordentlichen unix-shell gewähnt ist. Doch dem kann abgeholfen werden. Aktuelle Linux-Distributionen (und unter Windows CYGWIN) besitzen mit bash-completion eine einfache Schnittstelle zum Erweitern der Autocompletion.
Read the rest of “maven autocompletion für die shell (und windows)”
Continuum-1.1 aufsetzen
Friday, January 18th, 2008
Posted in: J2EE, System architecture, System engineering, continuum, java, maven 2, tomcat.
In diesem Post zeige ich, wie der Continuous-Integration Server Continuum mit tomcat 6 und MYSQL aufgesetzt und konfiguriert werden kann.
Hin und wieder ist man in der Universität mit der vergnüglichen Tatsache konfrontiert, dass es weder eine brauchbare vorhandene Anzahl an Entwicklungswerkzeugen gibt, noch dass sich irgend jemand – ausserhalb von Lehrveranstaltungen – um Prozesse in der Softwareentwicklung kümmert.
Sprich: Ein Projekt soll umgesetzt werden, und außer einem SVN-Account gibt’s nichts.
Bei einem Team von 8 Leuten ist das völlig unzureichend. Neben einem ordentlichen Issue tracking bin ich auch daran gewöhnt, Read the rest of “Continuum-1.1 aufsetzen”
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