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Vienna buying Office Licenses

When you just read the following sentence: "usage of a software, that can only be used together with the Internet Explorer". You already know the consequence that several hundreds Wienux boxes are gone.
Heavily disgusted by the waste of community money.

The online local newspaper has a comment that seems quite to the point to me: "If as sysadmin you introduce Linux you'll be accounted for eventual failures, while with softies people just accept the shortcomings and won't blame you."
German source: Wiener Inkompetenz in IT Managment.

P.S.: Wienux got setup by inexerienced people having no prior exposure to Open Source. The project setup included a calculated failure from the start.

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HTC Magic 90 days Android usage

I love the fact that phones are ready to get a decent OS. I bought the phone for better connectivity and to get GPS goodness. 90 days later seems a good time to review the pros and cons:

Pros:
• The phone sees updates (Android 1.6 has recent 2.6.29 build with much nicer battery status and search box).
• Easy to pick google calender together with useful gmail integration.
• Often use the phone for a quick websearch (cinema programs on the run, news, shop opening times, ..) - to lazy to power up real laptop.
• The touchscreen interface isn't too bad, but missed the nice resize effect seen on other touchscreens OS.
• Connectbot is a half decent ssh client.
• The consumed data is very low - never managed to touch the 1GB download bandwith limit.
• gmaps is fun to look up and helpful in finding directions.
• Last but not least important phone functions as easy dialing and good voice transmission are working.

Cons:
• The worst omission is a decent pdf reader. No way to read latest papers on arXiv.org.
• The next big missing thing that worked since years with mobile phones is bluetooth file sending and receiving out of the box.
• A more minor bugger - but still quite annoying: contacts sent to you as vCard don't get easily imported in contacts.
• The camera from the HTC magic is not really pleasant.

Of course Android still seems like an alien sandboxed Linux, but I must say that the average usage capability of the mobile phone is very nicely enhanced.

P.S. Using allmost daily also Google Talk, Ultimate Stopwatch & Timer, Finance, GPS Status and the ultra cool Google Sky Map.

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Particle Physics Planet

planet.teilchen.at is a shiny new selected blog roll of prominent Particle Physics blogs. Reading it should keep you updated on progress at the Large Hadron Collider (LHC) as well as on new discoveries in High Energy Physics, Astrophysics, Cosmology, advances in Quantum Chromodynamics (QCD), String Theory, Black Holes and many other hot physics topics. Most posts should be readable for scientifically interested public. Enjoy a daily read.

www.teilchen.at is the Austrian outreach site of Austrian particle and nuclear physicists. Authors are leading austrian scientists. The site just got relaunched with new features including some socialweb goodies (planet, share links on the bottom, better readability, noframes, ..). Happy if you send corrections or suggestions to mattems@teilchen.at.

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Debian Kernel Meeting

Vincent Sanders took notes during all our meetings at the Portland Linux Plumbers Conference: Debian Kernel Group Meeting. The condensed form has been posted today as Bits from the kernel team.

In the case of feedback I'd highly recommend to bring the Debian Kernel Mailinglist into the loop. The meeting decisions were done by the team as entity.

Responding to the deprecation of some external patches (Vserver, Xen Dom0): None of above patches have an upstream that supported the Lenny released version. Both have troublesome bugs in Lenny and thus are not in a condition one would expect from a stable release. If you want to help and have continued release of those beyond squeeze the answer is easy: Get them merged upstream. Openvz supports Lenny linux-2.6 version actively and promised to keep up with their work for Squeeze.

It has been a very productive meeting with lots of problems^Witems discussed. Interesting tracks for better cooperation between distributions, heavy technical tracks and loud BOFS. Quite some work has already been picked up since (Bug scripts, 2.6.31 experimental uploads, DEB_BUILD_OPTIONS=parallel=N support, package descriptions improvements, piuparts install fix, DFSG firmware clean, preempt, ..). So thanks a lot to Steve McIntyre (Debian Project Leader) for pushing the meeting, to Steve Langasek for setting it up on site and of course to everyone who contributed. Read aboves report for the full picture. :-)

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2.6.29 in sid

Latest Tasmanian Devil Linux 2.6.29 adds quite a lot of new features: Kernelnewbies 2.6.29 Overview.

Thanks a lot to the FTP Master Team for making possible the same day upload. Big thanks also for the regular testers of the rcX trunk snapshots.

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git: Throw away first X commits of a repository

Today got asked by a colleague, who wanted to throw away the early history of his repo. git allows you easily to rewrite the history start with:

echo $FIRST_SHA >> .git/info/graft
git filter-branch -f

Then with interactive git rebase you can rewrite this important initial commit. Of course you have to define $FIRST_SHA and your repo shouldn't be dirty.

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initramfs-tools new Lenny features

initramfs-tools design principle is to ship a generic initramfs. The design explicitly allows lots of customization through hook and boot scripts. A previous post focused on the history of initramfs-tools. Several contributors enhanced initramfs-tools since the Debian Etch release so the non exclusive new feature list:

• The initramfs contains all drivers/{ata,block,ide,mmc,scsi} modules instead of a stupid hard coded list. This gives bonus points for getting more future proof.
• Configurable small initramfs: The MODULES=dep mode walks /sys/ for the needed drivers of the specific box. This was the most wanted feature and is the new default for some Debian-Installer embedded architectures. The code seems in between well tested even if some corner cases might still emerge. The smaller initramfs is needed for specific bootloaders and helps on slow target boxes.
  For a even smaller initramfs you can kick busybox if you don't have an lvm2 root or don't need it's debugging tools.
• Quicker initramfs build: The update-initramfs command uses dpkg trigger and thus not every postinst update-initramfs(8) call leads to a new initramfs build. Also the build time got improved.
• Improved panic message (yes users need to be handhold at this point :).
• Potential debug log is visible after call to init(8) inside /dev/.initramfs/.
• update-initramfs got hardened against failure on update or ro partitons.
• The klibc utilities got worked on: chroot, fstype, ipconfig, mount, nfsmount sync.
• Fixed various bugs in NFS and networking setup due to incorrect option parsing.
• Allow to blacklist modules on boot by cmdline bootarg blacklist=modulename.
• Allow non root usage of mkinitramfs.

As bonus to some cleanup and docs update we have also seen a Ubuntu sync and are not too diverged.

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playlist sept. 2008
This time crushing for goooood voices across really different styles:

• Agoria - Think Different
• Ellen Allien - Rej (Feat. Ame)
• Trentemøller - Moan (Trentemøller Vocal Remix)
• DJ Brace - slammed preview
• p.tah - rasterpunkt
• Spiral Tribe - Breach The Peace
• Larry Heard presents Mr. White - The Sun Can't
• Groove Armada - But i feel good
• Modeselektor - The White Flash (Trentemøller Remix)
• Mono & Nikitaman - Fresse Halten - Selber Machen

double *bounce* triple *bounce*
For the youngsters among you who missed out Spiral Tribe there tunes still kick ass. Mono & Nikitaman were the best at the Viennese Donauinselfestival and should be seeeen life. Only the Dj Brace track is not yet released. p.tah is the mastermind of B Seiten Sound. Enjoy ;)

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OpenVZ Debian Linux images

Thanks to the Virtuzzo developers for forward porting the OpenVZ patch to 2.6.26. It uses a lot of the already merged namespace features (For interested peoples linux-next carries interesting sysfs patches). The openvz upstream merge statistic is impressive.

The namespace solution allows low overhead, while still running multiple Linux distributions in individual containers on the same box. Control over the network vitalisation is gained as a resource management for CPU power, I/O bandwidth and disk space. Live migration including snapshotting is possible too.

The Debian 2.6.26 Linux images will feature not only better Xen vitalisation support, kvm port to new archs, but also an opvenvz flavour. Please don't forget to install proper vzctl userspace support as the correct dependencies have not yet been added. Supported archs will start with both x86 and the ia64 archs. Tomorrows linux-2.6 Debian trunk snapshots will already build openvz. Thanks for your feedback.

P.S.: 2.6.26 is the targeted kernel for Lenny, we hope to convince Debian installer people to pick it up soonest - 2.6.25 is a not so bad backup plan as release hasn't fully approved 2.6.26 before extensive unstable testing.

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Open Source Graphic Drivers - oops less often

If you haven't read yet: Linux Graphics, a Tale of Three Drivers. The hard data is based on reports thanks to kerneloops.org. It matches quite evenly our bug experience on the Debian Linux images. As already stated "Open Source Graphic Drivers - They don't kill kittens". The unnamed company claims no need for open drivers.

Hardware vendors need not to forget that they don't get revenues from the drivers side. The conclusion is to buy hardware, where the vendor cares about Linux support. That means documents the hardware and enhances current free xorg with all needed goodies of enhanced power support and last but not least 3D acceleration support.

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"Open Source Graphic Drivers - They don't kill kittens"

People don't seem to get that once you load a 1MB binary blob into your kernel you are no longer running a free operating system. There is no way to fix it. No way to see what is going wrong.

Fedora 9 is shipping the latest xorg Release. It features major improvements for the Intel and Radeon drivers. The well known randr features got pushed even more. Plus gaining better 2D and 3D effects and important power saving improvements. Thanks to all the xorg hackers!

Big blame on a unnamed company that can't keep up with latest Linux (Xen gained paravirt_ops support in 2.6.24 - oh yeah but we are still on 2.6.18 state). To truly support Linux you'd have to first release your specs and then help existing xorg hackers. Even Via seem to have got the message lately after years of no transparence.

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2.6.24 in Sid

2.6.24 has been uploaded on Saturday and passed NEW on Monday. It will be soonest available for all archs. If we don't get enough test coverage or things go bad 2.6.22 will be the fallback for Etch+half. The images install in Lenny/testing just fine. So please give it a spin.

Known Issues are still missing VServer and Xen images, bnx2 + snd-cs46xx disabled due to firmware issue and ACPI userland still relying on old interfaces (for example #462305).

For more adventurous souls the kernel buildserver will continue to track latest Linus git daily snapshot (enhanced ext4 should land soon).

2.6.24 will also soon be pushed to Testing. I repeat this is not the real Etch+half kernel yet as there will be some config changes for it, but it is pretty close. Thanks for your 2.6.24-rc7 feedback.

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Testing Etch + 1/2 Kernel

2.6.24-rc7 is available on 5 architectures (amd64, i386, powerpc, s390, sparc). Please add the following line to your Lenny or Sid box sources.list and report back:

deb http://kernel-archive.buildserver.net/debian-kernel trunk main

This is not yet the real Etch + 1/2 kernel, but comes pretty close. According to our initial testing and user feedback 2.6.24 promises to be a great release. It will help Etch to have proper hardware support for newer hardware, has better power efficiency due to tickless kernel, enhanced wireless card support, the CFS scheduler and much more...

It is a Debian novelty to provide an supported optional Linux kernel upgrade for a stable release. This is not the final as due to incompatible user interface the Etch build will have the old firewire stack. Once aboves land in Sid and got broader coverage will announce the Etch snapshots. So please give it a shot on your Testing/Unstable boxes.

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Sony VGC Ubuntu Install
This Sony 22' display is fun to watch movies or tv. Installed Ubuntu on such a all in one desktop for a friend. As much as Debian improved visually thanks to newer Gnome and good upstream tango icons. I'm much less impressed by the visual appearance of Ubuntu 7.10. The compiz stuff is fun of course, but the replaced icon sets seem like a regression nowadays.
The logout buttons seem uglier and more misplaced then the usual Gnome ones, same story with the orange openoffice.org or the gnome menu icons. Restricted-manager failed in strange loops due to no initial network availability. Network-manager seemed to write settings to the correct file for static ip setup, but didn't actually set up the network. Also the "play Dvd" usecase seemed not much easier then in Debian. Only bonus is the python apt sugar "Add Remove Applications".

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playlist nov. 2007
I seem to rediscover old chill out classics like De Phazz and warm Marseillais Hip Hop in a foggy Viennese.

• Don Choa - Vies de chiens
• Fonky Family - Le plus grand des Voyous
• Aeto - B
• De-Phazz - Happiness
• Dj Brace - Mint
• N-jin - Crack Jack
• Pimbo - Roots remix
• Don Choa - Lune de miel
• Pink Martini - Sympathique
• Texta - So koennt's gehen

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happy git usage

Apparently Scott James Remnant in his article on version control systems confuses arch and git. One can only speculate that his short git usage stems from the pre 1.0 days, where you had to use higher level tools (called porcelain) to happily work on git. A funny anecdote is that Scott back in his dpkg hacking year promoted arch heavily.

Ubuntu^Wbzr propaganda spreads speed gains as big bonus of the last major releases. In order to be able to do that you have to start with a terrible baseline. Testing bzr on middle sized repos is no fun at all. The bzr pain inside launchpad must be beyond imagination.

Nowadays it is much easier to hack on mdadm than on lvm2. The reason is that later project uses rusty cvs. With git it is really easy to contribute back. Either you mail the patches or publish your repository. git will help you along on each way.

The other very big bonus of git is the big community around git. It is a community excited around building and delivering the best version control system. The git development does regular surveys on git usages and incorporates back the wishlists.

The most "funny" way to use git is to run it as cvsserver. You may believe me or not i have seen git cvsserver emulation usage in the wild.

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YAPC::Europe 2007
The current Perl confernce in Vienna seems to get the biggest YAPC::Europe ever, see q&d YAPC first day notes.

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linux-2.6 bugs cleanup part 2

Random notes on effective bugs cleanup on a bigger scale:

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Huawei E220 HSDPA usb modem

The usb modem works out of the box with current Linux 2.6.23-rc2 (why would you use older ;-).

usb 2-2: new full speed USB device using uhci_hcd and address 8
usb 2-2: configuration #1 chosen from 1 choice
option 2-2:1.0: GSM modem (1-port) converter detected
usb 2-2: GSM modem (1-port) converter now attached to ttyUSB0
option 2-2:1.1: GSM modem (1-port) converter detected
usb 2-2: GSM modem (1-port) converter now attached to ttyUSB1

[Dialer drei]
Modem = /dev/ttyUSB0
SetVolume = 0
Dial Command = ATDT
Init1 = ATZ
;Init2 = AT+CPIN=1234
Init3 = ATE1V1&D2&C1S0=0+IFC=2,2
Init4 = AT+IPR=115200
Init5 = ATE1
Phone = *99#
Stupid Mode = 1
Init8 = AT+CGDCONT=1,"IP","drei.at","0.0.0.0",0,0
Dial Attempts = 2
Username = xx
Password = xx

Current mood very happy. :) Aboves means connectivity almost everywhere in Austria due to A1 network fallback.

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linux-2.6 bugs cleanup part I

xorg and openoffice.org started with a cleanup of their bug reports. It is really great that compared to 2-3 years ago major cores of the Debian OS in unstable are quite in sync with upstream. Thus it is easy to forward to upstream the interesting part of bugs.

The linux-2.6 bugs count reached that weekend almost 850 open bugs. Seeing that it gets unmanageable I'll decided to get it down to a target of 100 bugs. I'll blog from time to time about the progress.

The process consists of pinging quite some bug reports against old Linux images and closing a huge swap of duplicate or no longer relevant bug reports. I expect the signal to noise ratio getting better once the bug count gets denser. The current side effect was to forward 1 patch upstream and to get 2 easy low hanging fruits fixed in latest linux-2.6 trunk.

Thanks to enabling CONFIG_BLK_DEV_IO_TRACE trunk gains support for the blktrace(8). blktrace does direct IO block layer tracing - see also blktrace guide.

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Fun with Legend Annotations in Graphs

E\sT\N \f{Symbol}t\0 f

E_T \tau f

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Happy switch from bzr to git
The cardinal reason for the switch is collaboration: git scales. During my bzr usage time of the last year i observed the following shortcomings of bzr:

Latest initramfs-tools repo is available at:
git clone git://git.debian.org/git/kernel/initramfs-tools.git

Thanks to tailor it is now possible to move from different version control systems. For git as target repository it is recommended to use latest upstream either directly via darcs or at least install the unstable version. The etch version throws strange python backtraces.

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ext[23] online resizing
The e2fsprogs package in Etch features the ext[23] resize2fs, see it in action on a mounted /usr partition:

nancy:/root# egrep usr /proc/mounts 
/dev/mapper/nancy_vg1-usr /usr ext3 rw,noatime,nodiratime,data=ordered 0 0

nancy:/root# lvextend -L+700M /dev/nancy_vg1/usr       
Extending logical volume usr to 4.68 GB
Logical volume usr successfully resized

nancy:/root# resize2fs /dev/nancy_vg1/usr 
resize2fs 1.40-WIP (14-Nov-2006)
Filesystem at /dev/nancy_vg1/usr is mounted on /usr; on-line resizing required
old desc_blocks = 1, new_desc_blocks = 1
Performing an on-line resize of /dev/nancy_vg1/usr to 1227776 (4k) blocks.
The filesystem on /dev/nancy_vg1/usr is now 1227776 blocks long.

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playlist march 2007

• Fistognosticated - Ella Baila
• Ellen Allien - Crosstown Rebels
• 4twenty - Wenn der Beat rollt
• Don Choa - La verité blesse
• Ricardo Villabos - Fiezheuer Zieheuer
• Jürgen Paape - Take this
• Oliver Hacke - Baked Bean Mix
• Henrik Schwarz - Leave my head alone brain rmxs
• Ellen Allien & Apparat - Bubbles
• Tiefschwarz - Issst (Nathan Fake remix)
• Lina - I'm not the enemy

Yeah i've danced all night in Florence on Ellen Allien sounds, explains why she shows up twice - great djane. :)

Meike, thanks for this funny "meme". By the way out of lazy web how did you fix the blosxom timezone toppost trouble? (urggs got title year wrong)

update: *doing* *doing* *doing* everywhere ;)

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Unbreakable IBM
Three letters corporations don't inspire confidence (junk code, big tactics, ..). Nevertheless Thinkpads i will miss you. My current workhorse is a x41 Thinkpad. The default model has a bad battery life. Yeah the x40 are cool and with much better battery life out of the box, but they need this mad atheros binary hal junk (the ath free replacement goes nowhere right now :(. No i won't taint the running kernel. So just buy a battery upgrade and be happy.
In August cycling i got badly hit by a car. Making a cool stunt on asphalt with a crashed helmet and hurt everywhere. The laptop being unprotected in backpack. No complaints from the X41. Throw it across rooms and it happily boots. Exposing it to dust did not cause any high pitch noise like some earlier Vaio.
As Thinkwiki will tell you the Hitachi hdd are not really worth to put data on them. I got mine easily exchanged 2x. I wouldn't care less thanks to git, imapd and frequent backups.
As you can probably imagine the story of unbreakable doesn't stop here, but i won't leak current experiences "nancy" had to endure. Anyway i wanted to join in the Thanks to all the peoples that make Debian the pleasure to hack and work on! Big props to the Release Team for coordinating the fine Etch product.

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linux-2.6 2.6.18 status
2.6.18-4 was uploaded on Sunday and should be soonest available after dinstall run for most archs. The ia64 build failure is fixed in svn thanks to Thiemo Seufer (ths). alpha is waiting for an updated gcc (see patch in #397139). s390 is currently broken by vserver, patch is awaited soon. linux-latest will be updated tomorrow and expect soon a 2.6.18-5, once those issues are cleared.
linux-image-2.6.18-2- is the Debian kernel team stabilized kernel. Please install it and report eventual bugs. If you know a patch from Linus git tree that fixes your problem even better name it. Thanks for your testing!
We had been quite busy to feed stable with patches that fit the Documentation/stable_kernel_rules.txt. Goodies like Xen, drm-i965 or ahci backport are shared with Fedora Core 6 release. Beyond that for example the r8169 patch series or ccisss support for 2 TB volumes got backported. Out of reach are destabilizing patches like the new 2.6.19 ACPI patches. Further backports are planed for the SUSE reiserfs 2.6.19 patches and vorlon has a fix in the pipe for the vga console driver on alpha.

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Early Userspace Fun
History
For the sarge release official kernel-images from the newly formed Debian kernel team came together with initrd-tools. initrd-tools Maintainer was jbailey. It saw some care from tbm, vorlon and me before the actual release. Remembering the flow of bugs and installation-reports it accounted for a huge number of install failures plus lacked many features the Red Hat mkinitrd had. Ubuntu got hit more directly as hoary released with a newer kernel than 2.6.8 and due to the initrd-tools devfs requirement.
initramfs-tools originated out of the need of a direct replacement. Inspired by an initramfs OLS talk jbailey had the goals of boot-time hardware detection using the nice and neat features the Linux 2.5 branch incorporated: The sysfs support of the Linux drivers allows an neat userspace daemon aka udev to coldplug them. udev is the replacement of a maze of slow shell scripts called hotplug package. The second big feature is the new initramfs format (the curious may want to read Documentation/filesystems/ramfs-rootfs-initramfs.txt of any current linux-2.6 source). For a boot loader initramfs or initrd is the same fish. The smaller and more efficient in kernel code makes the difference. The initramfs gets loaded much earlier, due to being only an cpio archive and not an fs allowing it to completely rule the rootfs search and mount. One initial assigned spec had the name "easy NFS root". The LTSP guys joined in and showed interest in incorporating their work.
Technology
initramfs-tools got default in Debian together when the first common linux-2.6 (2.6.15) package reached etch, powered all the Ubuntu releases from Breezy on and is used by the grml live-cd. Since archive inclusion almost a year ago it got much better support of all the various linux boot parameters (see man initramfs-tools or the "official" Documentation/kernel-parameters.txt), keeps an backup initrd around and has better block-based bootloader support (lilo, ..). klibc has been ported to _all_ the Debian release archs where it is in use and compiles fine on m68k and sh.
The initramfs-tools early userspace is very flexible based on it's hooks for initramfs build and boot. Thanks to alphix for the help on shaping the building blocks. There are initramfs hooks in cryptsetup, evms, dmraid, firmware-qlogic, lvm2 multipath, mdadm, usplash, .. Reviewers, uploaders and sponsors included fs, jbailey and Sesse. Most of the time it is sufficient and easy to test changes in qemu images (See slides workshop early userspace). The best wish of an early userspace is not to be remarked - aka happy booting. Nevertheless thanks a lot for the public support: Achieving Xen Disk encryption support in Etch, Popping my initramfs cherry, ..
Future
The latest initramfs-tools release seems almost ready for the upcoming etch release. The bug reports coming over from installation-reports are happily rare. Although the uuid based fstab generation solution is not yet integrated in the debian-installer. There are one or two known nitpicks left-over in the bts plus one bugger: udevsettle may exit to early, when not all the discs are ready for use. For grub there is a fail-over net, but which does not account for a to early md or lvm2 boot hook. Future initramfs-tools development will focus on an optional small klibc based Modules=dep hand walking /sys initramfs generation allowing better embedded support. grub2 will present run-time assembly challenges for the initramfs.

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network state monitoring
If something wierd is going with your network card and other methods fail to pinpoint (aka strace doesn't follow netlink) use as root (you'll get a nice log to stdout):

ip monitor all

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Set your email per git repo
Previously used export GIT_AUTHOR_EMAIL="bla@foo.org", but belows is much nicer as it can be set per repository.

git repo-config  user.email bla@foo.org

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Git server setup
On Debian take care to install git-core and optionally gitweb for the web interface.

 grep git /etc/inetd.conf
# git server
git     stream  tcp     nowait  root /usr/bin/git-daemon git-daemon --inetd --syslog --export-all --base-path=/var/cache/git

 grep git /etc/services
git             9418/tcp                        # git

 cat /etc/gitweb.conf
# path to git projects (.git)
$projectroot = "/var/cache/git/"

# directory to use for temp files
$git_temp = "/tmp";

# target of the home link on top of all pages
$home_link = $my_uri;

# html text to include at home page
$home_text = "/var/cache/git/indextext.html";

# file with project list; by default, simply scan the projectroot dir.
$projects_list = '/etc/gitweb.lst';

 egrep git /etc/apache2/sites-enabled/ssl
 ScriptAlias /git /usr/lib/cgi-bin/gitweb.cgi

mattems%2Fklibc%2F.git maximilian+attems

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git cheat sheet
Using git involves a decentral development even if central server is supported. Git is amazingly fast and scales very well. Some of the following commands may help to get used to it.

# clone the last revision localy
git clone /path/.git

# clone repo from remote pc                         
git clone git+ssh://user@host/path/.git

# create your own branch
git branch <username>

# set your email and name which will show up in the commits
git repo-config user.email "user@host.org"
git repo-config user.name "firstname name"

# show latest changes
git log
git log <file>
git show
git show <commitid>

# check which branch currently is active                                        
git branch

# create and use a test branch
git checkout -b test

<hackcodehackcompilehackcompile>

# commit either all or some parts related to the files
# please don't forget to add an meningfull desc
# the first line is the subject, all below the body
git commit -a
git commit file

# merge your test branch once your happy back to your branch
git checkout username
git pull . test

# undo all local modification as they b0rk
git checkout -f

# push your changes to the repo all can have access to
git push git+ssh://user@host/path/.git branch

# eventually delete the test branch
git branch -D test

# tag the current revision
git revert <commit-id>

# change commit message to last edit
# (yes that's the only one you can change others are protected)
git commit --amend

# delete last commit
git reset HEAD^

# cherry-pick a change from one local branch to another local branch.
git checkout <first local branch>
git log path/to/changed/file
git checkout <second local branch>
git cherry-pick <sha1 refspec from the previous 'git log' output>

# merging others changes
git fetch git+ssh//user@host/path/.git mater:incoming
git log mater..incoming
git checkout mater
git pull . bob-incoming

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Kexec allows quickboot
Kexec is handy for a quick and "real" test of the latest initramfs or the latest installed kernel. Install kexec-tools and be quite picky about how you pass the cmdline args. Be careful to launch the last execute from console. Sync and unmounting discs before is recommended. ipw2200 panics since ever on kexec, simple unload brings it back to life. When using in combination with initrd/iniramfs uname > 2.6.15 is recommended.

kexec -l -t bzImage --command-line="ro root=/dev/sda1" \
--initrd="/boot/initrd.img-2.6.16-1-686" /boot/vmlinuz-2.6.16-1-686

kexec -e

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Grazer Linuxtage 2006
The organizers managed to squeeze lots of interesting talks on a broad range of topics in one day. The bad news was the unmanned Debian booth, hope we'll do better in Vienna. Although i missed some funny talks like Funkfeuer Graz or an Puredata overview. I was busy doing my own talk and workshop. Homepage - Grazer Linuxtage. The atmosphere was warm and bright questions got asked. During the speakers dinners had an nice talk with mika about the good and bad sides of Debian. grml manages to do a lot. Tighter upstream integration will need more Debian work. Looking forward to that.
I even played billiard with mika's friends. :) Discovered in an never ending night the Postgarage. They played an Russian disco. Russian meant strange scratch effects, when switching lp and repeating songs. The chanson featured very sexy voices and the night was fabulous.

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302 moved
9 spannende Monate auf der WU. Nun Zeit mich wieder vollständig auf die Physik zu konzentrieren, dieses Blog wird auf der TU Wien weitergeführt, allerdings keine ahnung wo vorerst. Vermutlich kriegt es ein Link von Klausi's blog. Allen Lesern Danke + cu

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wine 16bit app needing a printer
Come across of an old legacy application that my chemical friend _must_ run. It analyses her experiments data. Shooting up the app with wine gave an stupid box with "Can not find an active printer":

wine LEGACY.exe
Invoking /usr/lib/wine/wine.bin LEGACY.EXE ...
err:dc:CreateDCW no driver found for L""
err:dc:CreateDCW no driver found for L""
Wine exited with a successful status

sudo apt-get install cups-pdf

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Ethtool - query or set your ethernet
Curious about which NIC hides in your box, use those commands, replace $iface with ethX:

$ sudo ethtool -i $iface
driver: tg3
version: 3.47
firmware-version: 
bus-info: 0000:40:00.0

$ sudo ethtool -S $iface

$ sudo ethtool -t $iface
The test extra info:
nvram test     (online)          0
link test      (online)          0
register test  (offline)         0
memory test    (offline)         0
loopback test  (offline)         0
interrupt test (offline)         0

sudo ethtool -s $iface speed 10

insmod 8139too media=0x01

ethtool -K $iface tx off

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LUKS crypto partition
LUKS is the Linux Unified Key setup. It is much easier to handle than previous cryptsetup. LUKS uses dm-crypt. Encrypt the partition with luks, you may want to run a bad block check before and overwrite it with random data. Out of simplicity this is skipped. Initialize the LUKS partition.

 cryptsetup  luksFormat /dev/sda2

 WARNING!
 ========
 This will overwrite data on /dev/sda2 irrevocably.

 Are you sure? (Type uppercase yes): YES
 Enter LUKS passphrase: 
 Verify passphrase: 
 Command successful.

cryptsetup luksOpen /dev/sda2 sda2
Enter LUKS passphrase: 
key slot 0 unlocked.
Command successful.

mkfs.ext3 /dev/mapper/sda2

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gdth unmainted scsi driver
_One_ disc had grown defects 2024. This made the controller hang and the fs are in poor state, what for is that ICP vortex controller?

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boot from usb disc
Take care to backup any data before formating your device. Copy your root. Change your current root device to the usb device. Of course your kernel or better your distro initramfs should have support for booting from usb disc.

mkfs.ext3 /dev/sda1
mount /dev/sda1 /mnt
find / -xdev | cpio -pm /mnt
echo "(hd1)   /dev/sdb" >> /mnt/boot/grub/device.map
perl -pi -e s/sda1/sdb1/ /mnt/boot/grub/menu.lst
perl -pi -e s/sda1/sdb1/ /mnt/etc/fstab
grub-install --install-dir /mnt /dev/sdb

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C Programming
Leider auf Deutsch dafür aber sehr klar und verständlich gibt es als openbook C von A bis Z und auf wikibooks C Programmierung.

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