Hi,

I'm sure this is possible... I'm just not sure how. Yet!

I have three machines. One is at home behind my firewall and has a dynamic IP. That's fine as I don't really want to open any ports on my home firewall. The second is at work sitting behind the firewall there- and I'm not even going to ask for approval to NAT an IP to my PC at work :-).

The third is in a data center far away. I only have a shell account on this server but other than that shell account not being root, I can do most anything I like with that account.

What I would like to do is SSH to this server simultaneously from my home and work PCs and, via this third machine, make them talk.

This is pure geekery so it doesn't matter what they say to each other; I just want to make them talk. Maybe one uploads a file and the other just pulls down that file. Maybe one opens a FIFO on the remote server and starts writing to it while the other starts snarfing that data. In fact, I like this latter idea best, I think.

How would you do it? What scripts (fired by cron if need be since I'm ostensibly away from at least one of the PCs at any given time) would you use?

It's actually pretty easy, have one open a local forwarded port and the other open a remote forwarded port then you can ssh from the local one to the other box.


ssh -L 2048:localhost:2048 user@central_host

and on the other
ssh -R 2048:localhost:2048 user@central_host

then from the one with the -L entry you can just ssh -P 2048 user@localhost and it'll connect you to the 2nd box via the central server

I use something like this to sshfs mount directories from the remote machine