# Reverse ssh tunnel:
# Host to access -> destination.host.net ; user=dest_user
# Source host    -> source.host.net      ; user=src_user
[email protected]$ ssh -R 22000:localhost:22 -f -N [email protected]
[email protected]$ ssh -p 22000 dest_user@localhost

# Reverse ssh tunnel:
# Host to access -> destination.host.net ; user=dest_user
# Source host    -> source.host.net      ; user=src_user
[email protected]$ ssh -R 22000:localhost:22 -f -N [email protected]
[email protected]$ ssh -p 22000 dest_user@localhost

This is very useful with dinamic IP connections. You can connect from the host with the dinamic IP, leave the tunnel open to other machine with ssh access and fixed IP and then connect to this machine on specific port (22000 in the example) to connect to the host with dinamic IP.

Also it can be useful in case you need access to a host which is inside a local network and you can't access from outside, but from this host you can connect to outside.

Reverse ssh tunnel

ssh

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