fail2ban problem and solution

If someone adds a lot of jails in fail2ban, then some of them may not start (errors in /var/log/fail2ban.log but not in the output !!!)
It seems that this is a common situation as it is described here:
http://www.fail2ban.org/wiki/index.php/Fail2ban_talk:Community_Portal

The problem appears in Debian Squeeze, too and the solution is in the previous URL in the section
fail2ban.action.action ERROR on startup/restart (near the end of page.

Unfortunately the solution is a bit of a hack... but at least it is a solution

 

I am writing the solution for completeness

In the file
/usr/bin/fail2ban-client

at line 145 you have to insert time.sleep(0.1) or time.sleep(0.05)
so :

BEFORE

Code:

 def __processCmd(self, cmd, showRet = True):
                beautifier = Beautifier()
                for c in cmd:
                        beautifier.setInputCmd(c)
                        try:

AFTER

Code:

 def __processCmd(self, cmd, showRet = True):
                beautifier = Beautifier()
                for c in cmd:
                        time.sleep(0.05)
                        beautifier.setInputCmd(c)
                        try:

 

FYI,

I had to add time.sleep(0.3) for it to work on ubuntu 8.04. Shorter times were still causing some errors.

sk

 

As I see, the most common setting is above 0.1
It's probably related with the cpu. The faster the cpu, the lower the time

 

solved

I finally found what was going wrong for this kind of error:

.

Initially, I tried the proposed solution, by editing /usr/bin/fail2ban-client, with no success.

Afterward, I read my fail2ban.log more carefully, and I saw this at start-up:

but I already read somewhere that Gamin is not working well.

So, I edited /etc/fail2ban/jail.conf to change backend from auto to polling, as auto was giving Gamin:

Code:

# "backend" specifies the backend used to get files modification. Available
# options are "gamin", "polling" and "auto".
# yoh: For some reason Debian shipped python-gamin didn't work as expected
#      This issue left ToDo, so polling is default backend for now
backend = polling

and after a

Code:

service fail2ban restart

, I have no more error.


this is solved for me!