Hi,
I have a Zoom X5v ADSL modem configured to forward outside connections
on port 22 to a machine on my internal network. This configuration works
fine, except that idle SSH sessions time out (as in just stop sending
packets - no TCP FIN appears) after a minute.
This behaviour doesn't appear on outbound connections, nor on
connections within the internal network. I suspect the modem's NAT
mechanism is trying to purge dead incoming connections, but it makes
life difficult for SSH which is intended to idle. This also didn't
happen on my previous modem (a Zoom X4) so I suspect it's a new
introduction to the X5v.
Trouble is, I can't find a setting to alter the NAT timeout. Zoom's
technical support suggests that "All Nate(sic) Timeout settings can be
modified on the NAT Page in the Admin Console". Which is certainly where
I'd look, but the only options are:
NAT: Enabled/Disabled (Enabled)
Mode: NAT / NAPT / Dynamic NAPT (Dynamic NAPT)
And some Session stuff for static NAPT. I reconfigured the modem to use
plain NAPT, thinking perhaps it timed out NAT sessions to free up more,
but that didn't help.
Any ideas?
--
Jay L. T. Cornwall,
http://www.esuna.co.uk/~jay/
PhD Student
Imperial College London