Bashscripts.org

I'm writing a bash script where I'm trying to chain a series of ssh servers together, then create a second tunnel inside the first one, so the data isn't decrypted between servers. The problem is, after I finish establishing the first tunnel, I'm inside the shell for the last server in the chain. I need to get back to a local bash prompt without closing that first tunnel, so I can run the command for the second tunnel.

I suppose I could open a second window (I'm using Cygwin) and find a way to automatically alt-tab between the two, but that's an awfully clunky solution. I have tried using flags to keep ssh from opening a terminal on the last hop, but that doesn't work- everything just hangs. Any ideas?

That's interesting! And it should work. Is the intent to get to that last machine and then tunnel directly back to the first machine, or does the reverse tunnel have to to through the original series of tunnels?

Yes, the idea is to create one tunnel that starts at my local machine and ends at the last server in the chain, then create a separate tunnel inside that one that goes straight from my local machine to that last server, so as to preserve data privacy on the hops in between.

The problem is that I can't create that second tunnel because I can't get back to the bash shell running on my local machine. I have to log out of the shell running on the final ssh server, which closes the first tunnel- no good.

Here's a diagram of what the finished connection should look like: