It’s common to have to ssh to firewall / gateway machine, then ssh to the machine you want to work on within a server network.
Typically you’d do this from your local machine:
$ ssh firewall.example.com Password: $ ssh my-private-host
I finally got bored of doing this, and created the following file: /usr/bin/sssh
#!/bin/bash ssh -oproxycommand="ssh -q firewall.example.com nc -q0 %h %p" $*
Now I can use the
sssh command to connect to hosts using the firewall machine as a proxy. Like most good hacks, this uses netcat.
$ sssh 10.1.2.3
Will connect me directly to a machine on the server network, via the firewall box. Seeing as it passes all parameters to ssh (the
$* bit) you can do port forwards and X-forwarding as usual too:
$ sssh -L 5432:localhost:5432 my-vm
This lets me tunnel the port for a PostgreSQL running on my development vm (
my-vm) in a single command. I have all my keys installed, so no passwords needed - I estimate this will save me about 60 seconds every day.