Kuo Kan Liang wrote:
> Dear all,
> 
> I have recently reinstalled my server (SL4.1, x86_64). I have
> encountered ssh timeout problem again. In the sshd_conf I have
> uncommented "TCPKeepAlive yes" and I have set "ClientAliveInterval 60".
> But I ketp got kicked out. I forgot what I did in the previous
> installation. The network hardware are the same, so there is no change
> in external firewall. What can be the problem?


I believe the default is 'TCPKeepAlive yes' - so you might want to
explicitly set it to 'no'.

If you believe it's a network problem, your first step might be to make
sure that the in-band keepalive packets (not the TCP out-of-band ones
which you are disabling) are flowing.

Ssh in with -vv, wait 60 seconds or so.

You should see these:

debug1: client_input_channel_req: channel 0 rtype keepalive@ openssh.com
reply 1

Are you seeing them?

Thanks,
Matt Cuttler