step ssh proxycommand hangs on shutdown

[maraino]

Discussed in smallstep/certificates#1143

^{Originally posted by jodygilbert October 26, 2022}
I'm using step-cli 0.22.0 on Windows 10 to connect to various Ubuntu servers. The servers are running Ubuntu 18.04 and 20.04.

I've noticed that if I reboot or shutdown the servers the connection hangs, it appears to be indefinitely but I haven't left it for more than a couple of minutes.

If I do this from a Ubuntu client the reboot works fine.

To get around this I've added the following options to the ssh config file, which forces the client to timeout and disconnect:

ServerAliveInterval 15
ServerAliveCountMax 5

I cannot tell if the issue is with the step client or the ssh client, any suggestions greatly appreciated.