Is there any way to list the tunnels that SSH clients connected to my OpenSSH server have set up?
I can use e.g.
lsof -i to show connections that are being actively tunnelled, but I'd like to be able to list tunnels that the clients have set up but may not currently be in use.
(It's just struck me that this may be an entirely client-side thing, i.e. the server only knows the client is set up to tunnel a port when something tries to connect through the tunnel, in which case the answer will be "you can't" - but I'll take that as an answer if so.)
(Background: I'm running a MineCraft server on a machine that won't be able to do much else while it's running. If I can monitor when users have tunnels set up, I can run up the MC server on demand.)