Keeping SSH open through firewall while idle

Hold on Cowboy

This blog post is pretty old. Be careful with the information you find in here. It's likely dead, dying, or wildly inaccurate.

We recently installed a Cisco ASA 5505 firewall where I work. Very powerful firewall, much too powerful for our needs, but oh well. The problem is that SSH connections from the inside to outside would timeout after 5 minutes. I think this was a problem with the NAT timeout settings, but I tried many, many different options with no success on the firewall. Then I discovered ClientAliveInterval for the OpenSSH server. You put that in your sshd_config file and restart SSH. It should work like a charm.

Did this help you out? It took me a few days to piece together all this information together, I hope this saves you some time (who knows, maybe the future me will be thankful I wrote this down). Let me know your thoughts. [email protected]