while true; do nc -z localhost 3333 >|/dev/null || (ssh -NfL 3333:REMOTE_HOST:5432 USER@REMOTE_HOST); sleep 15; done

Keep SSH tunnel open (PostgreSQL example)

Check if SSH tunnel is open and open it, if it isn't. NB: In this example, 3333 would be your local port, 5432 the remote port (which is, afaik, usually used by PostgreSQL) and of course you should replace REMOTE_HOST with any valid IP or hostname. The example above let's you work on remote PostgreSQL databases from your local shell, like this: psql -E -h localhost -p 3333

-1
By: rxw
2015-09-21 02:25:49

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    0
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What Others Think

OK, I can see this would be useful. A poor man's VPN. This would be OK if ssh kept crashing, but a if your connection's intermittent, a better alternative might be to enable: ClientAliveInterval, ClientAliveCountMax man 5 sshd_config
flatcap · 138 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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