From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sheldon Hearn <sheldonh@starjuice.net>
Subject: Re: SSH Connections Lost After 1 minute idle
Date: Wed, 14 Jul 2004 13:42:20 +0200
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To: Real Cucumber <monkcucumber@yahoo.com>
Cc: netfilter@lists.netfilter.org

On Tue, 2004-07-13 at 18:51, Real Cucumber wrote:
> I have a fedora firewall/router using iptables to
> forward incoming SSH packets to an internal server and
> it works great....however, only if the user does not
> remain idle for 1 minute.

If you're going to use SSH through a stateful firewall, you should
disable out-of-band keep-alives and enable in-connection keep-alives.

I use this in sshd_config:

# In older versions of OpenSSH, it's KeepAlive, not TCPKeepAlive
TCPKeepAlive no
ClientAliveInterval 30
ClientAliveCountMax 120

See the sshd_config(5) manual page for implications.

Ciao,
Sheldon.