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An example of checking out a git tag using Qt 4.6.0... Clone the Qt repository: $ git clone git://gitorious.org/qt/qt.git Show available tags: $ git tag -l output: v4.5.1 v4.5.2 v4.5.3 v4.6.0 v4.6.0-beta1 v4.6.0-rc1 v4.6.0-tp1 Checkout v4.6.0: $...


Building 64-bit/32-bit Debug&Release Universal Build... See my directions on checking out Qt 4.6.0 from the git repository if you do not already have the source code. Launch a Terminal and cd to the source directory. Run configure w/ 64-bit & 32-bit...


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** (beryl-manager:6606): CRITICAL **: can’t execute beryl-xgl: Success

Posted on : 25-05-2007 | By : Brandon W. King | In : Computers/IT, Error Fixes, Linux, Systems Administration



If you get the following error when trying to launch beryl-manager with KDE on Kbuntu 7.04 (Feisty) (likely with an ATI card from what I am reading):

** (beryl-manager:6606): CRITICAL **: can’t execute beryl-xgl: Success

The problem most likely has to do with this bug:


Which basically states that beryl-xgl was removed from beryl-core package due to how it is built.

Multi-thousand dollar experiment… Where did D:\ go?

Posted on : 24-05-2007 | By : Brandon W. King | In : Computers/IT, Error Fixes, Stories, Systems Administration

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Nothing like a little pressure to get you going in the morning. I came in to work today to find out someone had started an Affymetrix experiment but the analysis software would not start. About 2 hours were left before the experiment had to be run or it would risk the quality of the experiment and then would have to be repeated.

The problem… The 2nd hard drive which contained the analysis software was not being recognized by Windows. In comes Kubuntu live CD. Turns out the partition table was empty. I ran smartmontools to make sure the drive was still alive and it was. I tried running gpart to have it guess what the partition table should be and had it write a new partition table. Upon rebooting into windows the D: drive was visiable in My Computer, but it wanted to reformat it when I double clicked on it. Nice of windows to offer to reformat my drive isn’t it? Oh right, it has data on it that I want. Reboot back into Kubuntu… mount -t ntfs /dev/sdb1 /mnt… Hey, what do you know, all the files are still there. Kubuntu reading NTFS drive and Windows won’t… How ironic?

Any way, time was running out for the experiment, I knew the data still existed on the D: since Linux could read the data now… The thought came to my mind, maybe the partition table is wrong? So, I stumbled upon testdisk… testdisk /dev/sdb y done. I rebooted and Windows now could read and write from the D: drive again.

Purpose of this post: To remind myself and others to try testdisk when trying to fix a corrupted partition table. (Debian/Ubuntu(Universe): testdisk package)

xen + routed network (shorewall) + qemu

Posted on : 09-02-2007 | By : Brandon W. King | In : Computers/IT, Error Fixes, Linux, Systems Administration, Virtual Machines

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After setting up xen and configuring buildbot on a xen guest domain, I decided it was time to bite the bullet and setup shorewall to hide the xen guest domains behind a private network.

By the way, there are some nice guides on setting up shorewall with xen:

In the process I had to reconfigure Xen to use routed networking rather then bridged:

Changed (/etc/xen/xend-config.sxp) from:

(network-script network-bridge)
(vif-script vif-bridge)


(network-script network-route)
(vif-script vif-route)

After setting up shorewall properly and being able to log into two different Debian etch guest domains, I noticed that my previously working WinXP hvm was not starting up properly. When I looked into it further I found the following in /var/log/xen/qemu-dm.11384.log

domid: 20
qemu: the number of cpus is 1
/etc/xen/scripts/qemu-ifup: could not launch network script
Could not initialize device ‘tap’

Tap device cure (found here):

tunctl -t tap0

The final piece of the puzzle (since I’m using the routed script with xen)…

Comment out “brctl addif $2 $” from /etc/xen/scripts/qemu-ifup as mentioned by George in this mailing list thread.

UPDATE (2007Feb12): By doing the above two tasks, I was able to launch WinXP under Xen, but I did not have shorewall setup properly. To save time and money, I’m going with the simpler route of buying a hardware firewall/router. I will leave the information above incase it is useful to anyone (including myself) in the future.

Rescuing a Linux installation

Posted on : 30-01-2007 | By : Brandon W. King | In : Computers/IT, Error Fixes, Linux, Systems Administration

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In an attempt to save a system without doing a fresh reinstall by copying the contents from dying hard drive to new hard drive using external hard drive enclosure. This method seems to have worked well for me. I’m posting it as reference so others have a guide to work from and improve upon. I have only used this method once so make sure you know what you are doing if you follow the guide.

WARNING: Use the following formation at your own risk. Make sure you make proper backups. The following information may have errors or may not work properly and could possibly damage your system or cause the loss of data. Once again, use the following at your own risk. Research how to use each individual command so you know what you are doing.

Guide to moving a Debian or Ubuntu Linux installation from an old hard drive to a new hard drive without re-installing.

  1. Attach external hard drive
  2. Reboot computer into single user mode (i.e. rescue mode)
  3. Find the new device of the external hard drive (probably sda or sdb) dmesg | grep hd; dmesg | grep sd
  4. create new partions on new drive: fdisk /dev/sd(a,b, etc.)
    1. create swap partition
    2. create linux partition(s)
  5. initialize swap: mkswap
  6. create filesystem (I’m using ext3): mkfs.ext3
  7. Mount the new hard drive (referred to as /dev/sda2 from now on): mount -t ext3 /dev/sda2 /mnt
  8. Use debootstrap to get base install (ubuntu edgy example): debootstrap edgy /mnt http://us.archive.ubuntu.com/ubuntu
  9. Now the copy command: rsync -av –exclude=/dev –exclude=/sys –exclude=/mnt –exclude=/proc –exclude=/media / /mnt
  10. Make partition bootable: fdisk /dev/sda2 # use the ‘a’ option
  11. Shutdown system and put in the new drive.
  12. Get Grub working again:
    1. Insert Ubuntu or other Debian based live CD (Knoppix is a good choice too).
    2. Mount the new drive: mount -t ext3 /dev/hda2 /mnt
    3. Install grub: install-grub –root-directory=/mnt /dev/hda2
    4. chroot into new drive: chroot /mnt
    5. edit /boot/grub/menu.lst
      1. Update groot(hd0,) #if bootable partition changed (i.e. Was /dev/hda5 is now /dev/hda2… Old: groot(hd0,4) New: groot(hd0,1)
      2. Update kopt=root #if bootable partition changed (i.e. Was /dev/hda5 is now /dev/hda2… Old: kopt=root=UUID= or kopt=root=/dev/hda5 New: kopt=root=/dev/hda2 (NOTE: There is probably a way of getting the new UUID of the new partition, in which case you can just update the UUID option, but I don’t know enough about this yet to offer advice… Feel free to post a comment if you know more.)
    6. type: update-grub
  13. Reboot and hope everything works properly.

xen error: Error: Device 0 (vif) could not be connected. Backend device not found.

Posted on : 17-01-2007 | By : Brandon W. King | In : Computers/IT, Linux, Systems Administration, Virtual Machines

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Currently, I’m working on setting up Xen 3.0.3 on Debian Etch 64-bit. I installed the debian packages rebooted and used xen-tools to create a Debian etch guest domain. When I used xm create -c debian_etch_guest.cfg vmid=1 I got the following error:

Error: Device 0 (vif) could not be connected. Backend device not found.

I googled for the error and didn’t immediately find a solution to the problem (it may still be there in the search results), but as it turned out, the only thing I needed to do was install bridge-utils:

apt-get install bridge-utils

That’s it, now the guest domain boots without a problem.

CD Burning on Linux

Posted on : 20-12-2006 | By : Brandon W. King | In : Computers/IT, Linux, Software Endorsements

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Below is a screenshot I took from my setup for burning a copy of Debian Etch using K3b.

If anyone out there is looking for CD burning software for Linux, I would recommend K3b (k3b.org), which worked right out of the box (that being the apt-get box), auto-detected cd burner and write speed.


  • Used K3b in Ubuntu Edgy on an HP zd8000 Laptop.
  • Burned a copy of Debian Etch RC1 successfully.

Custom Debian Linux Kernel Debian package w/ initrd

Posted on : 06-12-2006 | By : Brandon W. King | In : Computers/IT, Error Fixes, Linux

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My attempt to build a new Debian Linux Kernel was thwarted by initrd! Thanks to Diane Trout mentioning that when using make-kpkg, to build a kernel image, doesn’t automatically make an initrd image. I investigated further and found out if you use –initrd, it will automatically generate the initrd image.

Below are the instructions for building a custom Debian Linux Kernel Debian package:

1) Install the following Debian packages (Need access to Universe repository for Ubuntu):

  • kernel-package
  • initrd-tools

2) Get the kernel source (choose version, I used 2.6.17):

apt-get install linux-source-2.6.17

3) Decompress /usr/src/linux-source-2.6.17.tar.bz2

4) cd /usr/src/linux-source-2.6.17

5) Switch to root if you haven’t done so already (sudo -s)

6) type ‘make menuconfig’ to configure your kernel

It may require installing libncurses5 and libcurses5-dev.

7) type ‘make-kpkg –revision 1.0 –append-to-version -custom –initrd kernel_image’

Feel free to change the revision number or and use something other than custom (or omit –revision and –append-to-version to use defaults).

8) type ‘cd ..’

9) dpkg –install linux-image-2.6.17-custom_1.0_amd64.deb

Except using the .deb package name which was generated on your computer.

10) Reboot and enjoy!

Global Warming: An Inconvenient Truth

Posted on : 06-12-2006 | By : Brandon W. King | In : Global Warming, Science

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I made the previous two posts on “Global Warming” from videos (and descriptions) I found on Google Video. I have been interested in the effects of “Global Warming” for some time now. The movie An Inconvenient Truth sparked my attention again. I highly recommend seeing the movie especially if you haven’t paid much attention to the “Global Warming” topic.

For those of you who don’t believe that “Global Warming” is happening, I have this question for you:

Are you willing to bet life on this planet as we know it, because you don’t believe Global Warming is happening? Maybe the outcome of Global Warming isn’t as extreme as some may believe it to, but maybe it will be worse. If Global Warming is real and we treat it has a scientific hoax, and don’t take action. Isn’t that worse than the scientists being wrong about the how extreme the changes will be on our planet? Isn’t it work taking action now “just in case”?

The Denial Machine

Posted on : 03-12-2006 | By : Brandon W. King | In : Global Warming, Science

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In the past few years, a hurricane has engulfed the debate about global warming. This scientific issue has become a rhetorical firestorm with science pitted against spin and inflammatory words on both sides.

This documentary shows how fossil fuel corporations have kept the global warming debate alive long after most scientists believed that global warming was real and had potentially catastrophic consequences. It shows that companies such as Exxon Mobil are working with top public relations firms and using many of the same tactics and personnel as those employed by Phillip Morris and RJ Reynolds to dispute the cigarette-cancer link in the 1990s. Exxon Mobil sought out those willing to question the science behind climate change, providing funding for some of them, their organizations and their studies.

Blue Man Group on Global Warming

Posted on : 03-12-2006 | By : Brandon W. King | In : Global Warming, Science

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Description from Google Video:
Your attention please. Thank you for choosing earth as your planetary vehicle. We hope you enjoy the many wonderful features of this planet, as you hurtle through the cosmos. Please note, that in the event of continued inaction in the face of global warming – your seat cushion can be used as a flotation device. Please take a moment to locate this planet’s emergency exits. As you can see, there aren’t any!