Hittade en bra howto på SSH tunnlar
So in our example, we want to connect from a->b and then a connection will be made on our behalf, from b->c. So how does this manifest itself in reality. Let’s look at a typical ssh command line, which would be run on a.local, to achieve what we have described.
ssh -nNL 4800:c.mailserver:110 b.sshserver -l sshuser