While running my ssh server with Fail2ban, I decided to take a look in the log files to see if everything was working. It was not.

Here is the solution to stop errors like: fail2ban.server : ERROR Unexpected communication error on ubuntu 9.04 with Fail2ban from the repo\'s.

First we need to install python2.5 because Ubuntu 9.04 has 2.6:

sudo apt-get install python2.5

Confirm with Y where needed.

Now, we need to edit the fail2ban binary so that it makes use of python2.5:

sudo gedit /usr/bin/fail2ban-server

Change the first line (#!/usr/bin/python) to the following:

#!/usr/bin/python2.5

Save and close the file.

Now restart the fail2ban service. Note: sudo /etc/init.d/fail2ban restart did not work for me, so I did the following:

sudo /etc/init.d/fail2ban stop

sudo /etc/init.d/fail2ban start

And If you check the log files now (vim /var/log/fail2ban.log) you will not see the error anymore.

Good Job :D

Note: Made with help of: http://ubuntuforums.org/showthread.php?p=7408681.