How to launch rdesktop with a custom screen size:

rdesktop -g 1024x768 -k de -u <user> -p <password> host.domain:<port>

Now that was easy, wasn’t it? Blessed be the man command 8-P

If you’re on Linux, this may have happened to you: Google Chrome’s flash plugin all of a sudden sets the audio playback volume to 100% whenever you play a youtube video which may end up in serious sound distortion for all other apps on your system, including google chrome.

Here’s how to fix it:

– make sure you have the “pavucontrol” application install (pulse audio volume control panel)

– with a youtube or other flash video running, fire up pavucontrol, it should look something like this:

https://dl.dropbox.com/u/1983539/pavucontrol.png

Simply drag the “chrome alsa” volume slider to 30% or so and you should be all set to enjoy non-distorted sound in both chrome and Linux (Ubuntu 10.04 in my case) again.

For a job-related project I’ve been fiddling with openssl to create a new CA instance for self-signed certificates.

Initially I had problems importing our root CA cert into firefox, but finally got it working after some googling. The main problem is that by default on Red Hat 5.x, the file /etc/pki/tls/openssl.conf has the following entry set to FALSE:

basicConstraints=CA:FALSE

So you when you create the root CA certificate using

/etc/pki/tls/misc/CA -newca

the root ca cert will end up with the above constraint set to FALSE. Firefox doesn’t like that and will consequently refuse to import the certificate as a new CA.

Solution: Simply fire up your text editor of choice (I prefer GNU Emacs ;)) and change the line above in your openssl.conf file to read

basicConstraints = CA:TRUE

and you should have no problems importing the certificate into Firefox and other browsers.

Remember to undo the change before you generate your first self signed server certificate or you may run into other problems when trying to use these certificates in web- or mail servers.

It’s also worthwhile checking the other stuff in openssl.conf if you want to change settings such as default key length or certificate validity periods.

I recently updated my main Linux machine to Linux Mint Debian Edition (LMDE) because I’m not happy with Canonical’s “unity” strategy and trying to kill Gnome 2.x outright instead of fixing what’s wrong with it.

Most stuff worked well out of the box, but somehow the flash plugin could no longer play sounds.

A post on the Linux Mint forums was especially helpful in fixing this issue. As the “root” user, issue the following command:

touch /etc/asound.conf

Then, open the above file in your favourite text editor (mine’s “emacs”) and add the following lines:

pcm.pulse {
    type pulse
}
ctl.pulse {
    type pulse
}
pcm.!default {
    type pulse
}
ctl.!default {
    type pulse
}

Save the file and reboot your system and from then on, the flash plugin in Firefox / Chrome / what have you should be able to play sound again.

Just the other day, my favourite browser started acting up on Linux Mint 10: whenever I started google chrome or chromium, the entire window would lock up and I’d have to kill the process using xkill.

I decided to start with a fresh set of preferences which is no biggie as google chrome’s nice sync feature makes it a snap to restore one’s favourite bookmarks, accounts and so on, so here’s what I did:

Open up a shell and type the following commands (make sure neither chromium nor chrome are running beforehand):

$ cd ~

$ mkdir backup

$ mv .config/.chromium .config/google-chrome backup/

Start google chrome, and you should be greeted by the familiar welcome screen.

Caveat: Only tried this on Linux Mint 10 (Ubuntu based), YMMV depending on the distro of your choice.

I just did some rudimentary benchmarking of various Linux filesystems on Ubuntu 10.10/32 bit, doing an rsync -av of /usr /about 3,5GB of data) to a USB-connected, freshly formatted ATA drive (Seagate Barracuda 750g), here are the results (caveat: I used the system for web browsing and some shell stuff during the runs, so take the numbers with a large grain of salt):

xfs: 10m 1sec

jfs: 9m 5sec

btrfs: 7m 29sec

ext4: 6m 47sec

All filesystems were formatted using default parameters.

If it wasn’t for the long delay creating a largish ext4 fs as it writes its inode tables, I guess I’d be using ext4 more! 😉 Nice work also on btrfs, I guess there’s some more performance to be gained as the file system comes of age.

Recently, I had to scale down a series of images in different resolutions down to a web-friendly 600xsomething size so I could upload them to Zope’s internal Medusa ftp server without having to wait hours or breaking the resulting picture page with humongous images. Here’s how I did it, assuming the pics reside in a directory called “picdir” in my home directory:

cd ~/picdir

mkdir web # create a temporary dir to hold the scaled down images

for f in *jpg *JPG ; do

 convert -geometry 600x "$f" web/"$f"

 #convert to 600px width at most, let convert figure out the rest

  echo $file

done

Of course, this only works for landscape format pics, portrait format pictures will end up slightly larger because of their greater vertical size.

Hi folks,

here’s something I came across while playing with Ubuntu 10.04 Lucid on my eee pc 1005p: Apparently, to get the “disable touchpad” function key working (fn-f3), you have to deselect the “disable touchpad while typing” setting in the gnome control center-> mouse input settings.

I found that with the above setting enabled, if you hit the function key to disable the eee’s touchpad, it will get re-enabled on the first keypress.

Hope that fixes the problems for some of you using the eee pc 1005p model.

Just playing around with Jolicloud on my eee 1005p, and I really like what I’m seeing. Ok, it’s still based on Ubuntu 9.04, but seems to be a rock-solid netbook os featuring great looks for the n00bs and configurability for the hackers alike. Keep up the good work!

More on jolicloud: http://www.jolicloud.com/

Just trying to hack my way into Mercurial, a python based SCCS

I recently updated my work machine from Mint 8 to Ubuntu Lucid and noticed in the process that Lucid comes with the very latest Bacula version, namely 5.0.1. Sadly, this client is incompatible with what we run at work, so I had to figure out a way to “hold” the packages at their karmic versions which still worked fine on lucid. Thanks to the excellent Ubuntu docs, I managed to put those packages “on hold” using the following commands:

echo bacula-fd  hold | dpkg --set-selections

echo bacula-common  hold | dpkg --set-selections

Once you run apt-get update, you’ll see the newer versions being held back.