This is one quick tip about how to use transparent ssh proxying via a jumphost.
For a while, I have been using netcat to do this. Then when I eventually upgraded my macbook, it stopped working, and the error message ‘Protocol Mismatch’ was anything but helpful. Since it took me a while to find this fix, I thought I will put it here.
It took a while to realize that transparent proxying in ssh doesn’t need netcat anymore. Its built in.
For a single line proxy, this works
ssh -t <jumphost> -t <destinationhost>
If you would want to automate this via ~/.ssh/config, here’s an example.
host <destinationhost>
user <username>
ProxyCommand ssh tpgateway -W %h:%p 2>/dev/null