openssh unix dev - Jan 2001 - Connections automatically timeout?

Hi --

Recently set up OpenSSH on a number of machines that I'd been using
ssh2 on (illegally, it turns out... gotta read the small print!).
OpenSSH is working great except for one small thing.

If I leave an openssh connection untouched for a few hours, it seems to
automatically disconnect.  I don't see this behaviour with ssh.com
ssh, either v1 or v2.

I have Keep-Alive set to 'no' for both openssh and commercial ssh, but
can't find any other possibly relevant directives.  Am I missing something
obvious?

Thanks!

	Gary

Hi,

On Wed, Jan 17, 2001 at 09:15:10AM -0700, Gary Shea
wrote:
> Recently set up OpenSSH on a number of machines that I'd been using
> ssh2 on (illegally, it turns out... gotta read the small print!).
> OpenSSH is working great except for one small thing.
> 
> If I leave an openssh connection untouched for a few hours, it seems to
> automatically disconnect.  I don't see this behaviour with ssh.com
> ssh, either v1 or v2.
> 
> I have Keep-Alive set to 'no' for both openssh and commercial ssh,
but
> can't find any other possibly relevant directives.  Am I missing
something
> obvious?

This sounds like a problem I experienced, wherein a connection that
was inactive over a period of time "hangs" because an intermediate
router that was masquerading IP addresses timed-out the masquerade
table entries due to inactivity (30 minutes in my case).  The solution
is to:

1.  enable keep alive on either the client or server (in my case, it was
    logical to do both, as it was an issue for both incoming and outgoing
    connections.  That is:
	KeepAlive yes
    in both sshd_config and and ssh_config (or $HOME/.ssh/config).

2.  Fix ssh and sshd so that they honor the keep alive request for
    both protocol 1 and 2.  See my previous email to the list of Jan 12
    which has relevant patches, subject: Re: Socket options not properly
    set for ssh and sshd.  I'll forward that off-list.

    I see by checking out top-of-tree Openssh with anonymous CVS that
    as of yesterday, the patch is in the OpenBSD version of Openssh,
    but not yet in the portable version.  The patch is not yet in any
    released version.  (I'd expect to see it in the V2.4.0 release).

On Wed, 17 Jan 2001, Gary Shea wrote:
> Hi --
> 
> Recently set up OpenSSH on a number of machines that I'd been using
> ssh2 on (illegally, it turns out... gotta read the small print!).
> OpenSSH is working great except for one small thing.
> 
> If I leave an openssh connection untouched for a few hours, it seems to
> automatically disconnect.  I don't see this behaviour with ssh.com
> ssh, either v1 or v2.
> 
> I have Keep-Alive set to 'no' for both openssh and commercial ssh,
but
> can't find any other possibly relevant directives.  Am I missing
something
> obvious?
 
Is there a router performing NAT or a masquerading firewall between the
client and the server? These frequently timeout quiescent connections.

-d


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