How to kill a process running in detached tmux on a server?

I am logging in to a processing farm. There are multiple machines I can log in through(multiple physical machines acting as a single server unit I am logging to through ssh). If I start a tmux session, detach and then log out and log in, I can not attach to the session, because I am logged in through a different machine. My question is, how do I find out what machine am I logged in through and what can I do to connect or at least kill the tmux session?