Mosh with port forwarding (like SSH)

Question

When connecting to my development server via ssh, I can forward remote ports to local ports via:

ssh my-user@example.com -L 5432:localhost:5432

However I'd rather use mosh because my connection tends to drop. I tried extending my usual mosh command (that works) with the --ssh parameter:

mosh --ssh "ssh -L 5432:localhost:5432" my-user@example.com

Which gets me connected without error - but doesn't do anything for my ports.

Is there a way to make port forwarding work when connecting via mosh?

Answer 1

I found an open issue for this exact feature at Mosh's GitHub. And an open bounty at bountysource currently at $616.

So it looks like it's not possible yet.

--

As a workaround for my SSH disconnect issue I added the following lines to my server's /etc/ssh/sshd_config:

ClientAliveInterval 60  # send null packet every x seconds to clients
ClientAliveCountMax 720  # time them out after doing so y times

Followed by a restart of the SSH daemon and a re-login via SSH.

sudo /etc/init.d/ssh restart
sudo service ssh restart
sudo systemctl restart ssh

This of course doesn't help with situations like changing cell towers on mobile connections like mosh does.

Answer 2

This feature is not yet supported. However, there is always the workaround that you can run an SSH session in parallel.

Answer 3

Mosh opens an ssh session to setup the initial connection. Keeping that open would be a good way to maintain port forwarding while still using mosh for interaction. I've tried setting this up without any success:

mosh --ssh="ssh -fN" # hangs forever
mosh --ssh="ssh -f" # ssh gets terminated