SSH Tunnel using PuTTY no longer works after server change

Solution 1:

At rwired's request, I'm reposting my previous comment as an answer, which was:

Can the remote Linux server establish outbound connections to TCP port 80? For instance, if you "telnet www.google.com 80" from the server, do you get "Connection established"? Or does it just hang?

The intended implication was that something is blocking the outbound connection, which rwired discovered was indeed the case.

Solution 2:

Set

GatewayPorts yes

in your sshd_config. It defaults to "no", which prevents you from using remote port forwarding (ssh -R) to any address other than the remote SSH server itself.