I am using Centos 6 and iptables-1.4.7-9.el6.i686

I want to block regular attackers through the iptables.
This is what I have used, but it doesn't seem top stop the attacks:
btw, I am using fail2ban.

Any advise will be very welcome.

Thanks,

Fail2ban already contains default configuration for blocking through the firewall. So unless you want change to a different table (raw versus filter) or better performing method (ipset instead of iptables) you don't need to fiddle with iptables rules.


You haven't told us what kind of attacks these are, if fail2ban was configured to catch these, what fail2ban logs about attacks and if rules get added to your iptables rule set.

can F2B catch CIFS buffer overflow attack? or an attack that is ingress targeting Flash player?
different tools for different purposes, F2B is just one tool with limitations, etc.
define your requirements for protecting the system, then find the right tool(s).

Hi Guys...
Thanks for taking the time to reply to me.
I have now moved the iptables rule to the top and all the intrusions have stopped.

Problem solved.

Thanks again for your replies.

i am curious to know how you think iptables is stopping "intrusions". if the src IP changes are you still ok?

Hi Linux_Kidd ...
Thanks for your interest.
No. I am not covered.
However, I do have fail2ban running, which stops intrusions.
The reason that I wanted to ban a particular ip number, is that it was persistant in it's attempts. Each time it was banned I got an email telling me. After a couple of weeks of getting a stack of emails, I decided that I wanted to ban the ip number before it got to fail2ban.
I was concerned that if this ip number was persistant enough, it may eventually crack my security. Probably not, but I wanted to be sure.
Dropping it in iptables did that. I don't have any trouble now.
Hope this explains it for you...

if say attacker has a bunch of bots and each bot is executing different piece of the attack (like brute force ssh from a-c on bot1, and d-f on bot2, etc etc), fail2ban is not a 100% useful tool in protecting against this type of attack.

the Q from unSpawn was never answered,,,,,, what type of attacks are you talking about?

I didn't look at the logs.
I get an email every time an ip gets banned by fail2ban, and one particular ip number was showing up every time.
When I banned that ip number in iptables, I didn't get any more bans by fail2ban.
Maybe it was the same attacker using different bots, and gave up.
All I was interested in was stopping any attacks being picked up by fail2ban. And that has been achieved.
Hope this explains it better.

in your /etc/fail2ban/jail.local stanza for each, is what I use.

I don't have a jail.local. I only have jail.conf.

Can you please enlighten me ???

Thank you.
I will study it more and better when I return from holiday.

You're very welcome.

Basically, the process is this.
Copy the jail.conf to preserve your settings in case of an update/upgrade to fail2ban.
Any .conf files installed (and even modified) after installation will be lost if/when f2b is upgraded.
It's not too late to copy it now (post install or modify) using

1 members found this post helpful.

Thank you habitual..

I have done I will be going away for a week tomorrow morning, so I will take a look at the link that you sent when I get back.

I'll be "here".

subscribed with interest...