ssh tunnel with auto reconnect ability

while [ ! -f /tmp/stop ]; do ssh -o ExitOnForwardFailure=yes -R 2222:localhost:22 target "while nc -zv localhost 2222; do sleep 5; done"; sleep 5;done

By: jianingy
2009-02-08 12:45:43

What Others Think

check out the -N option to ssh Do not execute a remote command. This is useful for just forwarding ports (protocol version 2 only).
devnull · 704 weeks and 4 days ago
You might want to use ~/stop or ~/.stop as the file to stop your loop, since it's usually possible for anyone on the system to reach /tmp (doesn't matter on a single-user box, but it's generally a good idea to stay in your home directory anyway).
mulad · 703 weeks and 2 days ago
Or just run the who shebang out of /etc/inittab with the "respawn" option. See
Hal_Pomeranz · 676 weeks and 5 days ago
Dunno about this "target" piece in your command. I assume your command is meant to provide a way to keep trying to connect if it fail. Inspired of this, I wrote my own command that help me automatically reconnect immediately after the connecting pipe is broken: while true; do if ! nc -z localhost 7070 > /dev/null; then ssh -N -D -p 22; else echo 'not connected, retry after 10 seconds...'; fi; sleep 10; done
fwonce · 480 weeks ago
Were there clues I didn't see? life insurance virginia beach
tillyracker · 64 weeks and 5 days ago
seofox · 38 weeks and 2 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?

You must be signed in to comment.

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.


Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: