Archive for the 'debian' Category

Desktop Linux distributions popularity 2007

Which Linux distros do we use on our home or office desktop system(s)?


More information is here.

Secure shell (ssh) session timeout

I’ve noticed that when I keep ssh sessions that I opened before untouched for some period of time (like 30 minutes) they become frozen and as a result I have to close ssh terminal and start a new connection. To prevent such situation I found several tips:

1) Start some utility updating the screen before leaving ssh session untouched. I usually use watch -n 1 ‘date’ that shows current date every second. Other simple way is to send icmp requests to some host, e.g. ping

2) Increase ssh session idle time by

echo “7200” > /proc/sys/net/ipv4/tcp_keepalive_time

I’ve checked these tips with Fedora Core, CentOS, Debian and Ubuntu but I’m completely sure that it applicable also for other Linux distributions. First tip (ping) can be used in Unix also.


How to create custom linux ISO image?

It’s rather trivial task to make some changes into already burned installation or live CD. It may be performed to add some files to this CD or edit files on it. In any case it’s impossible to loop mount .iso file and then save it as iso9660 filesystem is read-only.

So, just mount your CD or iso image to some directory by commands:

sudo mkdir /mnt/image

sudo mount /dev/cdrom /mnt/image


sudo mount /path/to/your.iso /mnt/image -o loop

then copy it’s contents to some directory:

mkdir /tmp/newiso

cp -r /mnt/image /tmp/newiso

After this you can modify any files in /tmp/newiso, add files, delete them. After modifications are done, create new ISO image to be burned onto CD (or kept somewhere for a rainy day):

cd /tmp/newiso


sudo mkisofs -o /tmp/new.iso -b isolinux/isolinux.bin -c isolinux/ -no-emul-boot -boot-load-size 4 -boot-info-table -J -R -V “new iso name” .

After mkisofs is finished new ISO file will be created at /tmp directory.
It works in any Linux distributions like Ubuntu, Debian or Fedora.

Funny aptitude trick in Ubuntu and Debian…

Ubuntu and Debian aptitude trick (eggs)