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Polk
26th March 2009, 02:16
I'm getting this error in Putty:
Server unexpectedly closed network connection

Anyone knows how to fix it? All search results show to turn off UseDNS no but I'm not even using dns. I connect to IP directly. Anyway, tried that and it didn't work.

I'm able to connect from other locations. just one computer got blocked. I can't find anything in logs, tried to reinstall ssh, ssh-openserver, fail2ban.

I'm on Debian Lenny installed using Perfect Server manual.

falko
26th March 2009, 19:36
fail2ban
How many failed login attempts did you make from this computer? I guess fail2ban is blocking that computer.

Polk
26th March 2009, 19:48
How many failed login attempts did you make from this computer? I guess fail2ban is blocking that computer.


that's what I thought too. I did about 5 failed connections. I tried to uninstall fail2ban and also there was nothing in the iptables -L

Any ideas?

falko
27th March 2009, 15:32
http://debianclusters.cs.uni.edu/index.php/Fail2Ban:_Preventing_Brute_Force_SSH

Polk
27th March 2009, 17:48
Thank you. I found that link online too. And followed the steps. I did not have blocked IP in my list.
I also did apt-get remove fail2ban.

falko
28th March 2009, 20:26
And connecting from another IP works?
Is the IP listed in /etc/hosts.deny?

Polk
28th March 2009, 20:32
And connecting from another IP works?
Is the IP listed in /etc/hosts.deny?

Yes, I was able to connect from other IPs and yes, my blocked IP was listed there. Thank you so much! I removed and it's now working again!

Thank you!