1

I know how to prevent a SSH idle timeout on client and server side, but is there a way to configurate this on gateways?

I am asking because our company network consists of hundreds of clients and dozens of servers. Configurating all ssh_config files on all servers would be a lot of work.

Is there an easy solution to my problem?

  • Do you mean on switches and/or routers? – user36472 Sep 22 '17 at 7:33
  • 2
    You should specify which brand and model of equipment, as the answer is dependent on this. The answer from Hung Tran is valid for Cisco stuff. – JFL Sep 22 '17 at 7:57
  • Most SSH session use keepalive to keep a session working (e.g. through NAT), so detecting 'unused' SSH sessions on a central router (or better: firewall) can be quite complex. Any answer will depend on the equipment used. If you have that many hosts to configure, you should consider deploying SSH config using a central management system like ansible, chef, puppet, salt, etc. – Teun Vink Sep 22 '17 at 12:23
  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer. – Ron Maupin Feb 21 '18 at 16:37
1

Updated my answer as it is for Cisco:

Under line vty 0 15 configuration part, you can set exec-timeout to zero (0). Zero means the telnet/ssh session remains alive until you close it.

line vty 0 4
 exec-timeout 0
 ...
line vty 0 15
 exec-timeout 0
 ...
  • This only fixed connection to the router, not SSH connections routed by the device, which seems to be what the OP is asking. – Teun Vink Sep 22 '17 at 13:38
  • This is not recommended to have on a production environment, as sessions can stuck and you will be unable to reconnect to your router once all of available sessions will be depleted. – Andrey Prokhorov Mar 21 '18 at 15:46
  • @AndreyProkhorov Agreed! – Hung Tran Mar 21 '18 at 22:18
0

@JFL is right. There is no generic solution for gateways as they are just forwarding the connections. But the manufacturer do provide solutions for such configurations on top of a basic router/gateway/switch. Hence different products provide different settings to achieve this and some don't even provide anything like this.

Like Cisco has something @Hung Tran mentioned.

Brocade provides something like this ::

device(config)#ip ssh idle-time 30

Syntax: ip ssh idle-time minutes

If an established SSH session has no activity for the specified number of minutes, the Brocade device closes it. An idle time of 0 minutes (the default value) means that SSH sessions never time out. The maximum idle time for SSH sessions is 240 minutes.

  • Does a RV325 Gigabit Dual WAN VPN-Router support this function? I couldn't find any option to prevent ssh timeout in the firewall settings. – Mio K. Sep 22 '17 at 10:52
  • try through CLI. – enZyme Sep 22 '17 at 11:28

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.