X2Go Session Handshake

To demonstrate an X2Go session startup (and suspension, resumption, termination), this page describes the manual steps required for launching an X2Go session.

On start of an X2Go session 3 tcp ports for ssh tunnels (graphic, sound, sshfs) are reserved. The values of these ports are stored in the X2Go session database and used by X2Go Client every time an X2Go session gets resumed. Sometimes it can happen that one of these ports is already used by another application after the session had been suspended. As result, X2Go Client will be unable to resume such session or start sound or sshfs tunnel. To avoid this problem X2Go Server (>= 3.1.0.0) will verify if these ports are still unused before the session will be resumed. In other case new ports will be reserved. The new port values will be updated in database and sent to the X2Go Client.

IMPORTANT: Older versions of X2Go Client will be compatible with newest X2Go servers. If ports have changed between suspend and resume of a session, older X2Go Clients will try to reconnect and fail.

But on the next attempt, X2Go Client will retrieve the updated port values from the X2Go session database.