intermittent sshd connection problem in Linux

From: LazyAnt (soporte_altex_at_hotmail.com)
Date: 02/26/04 

Date: 26 Feb 2004 14:46:49 -0800

Hello,

I'm running sshd (OpenSSH_3.5p1) on a Red Hat Linux 9 server (kernel
2.4.20-8smp) and sometimes the users or myself cannot connect through
ssh.

The error I get is "connection refused by the server".

It's an intermittent problem and I cannot reproduce it.

It's not a client problem or a network problem, as:
- I've tried with several clients (puTTy, cygwin, ssh) from Windows
and Linux.
- I can see the requests with tcpdump in the server
- I can see the half connections to ssh port in the server with
netstat

The sshd service is running, and I can connect through it from another
private network interface, even when it's not working from the public
one.

- There's nothing significant in the /var/log/secure or
/var/log/message

- When I run sshd in the debug mode, if I try to connect from the
public interface nothing happens, but it works properly when trying
from the private one.

- It's not a firewall problem, I tried turning it off also.

- I'm not running any other network services but sshd.

- The sshd configuration file is the default one.

After some time I can connect as if nothing happened.

any suggestions?

thanks

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