From Python, I needed to find a process that was performing SSH tunneling on port 8080 and kill it.

The following works in Bash:

ps aux | grep [s]sh.*:8080 | awk '{print $2}' | xargs kill -9

The grep [s]sh trick ensures that the grep command itself won’t make it through to awk.

Here’s what I came up with in Python using psutil:

def kill_port_forwarding(host_port):
    ssh_args = ["-f", "-N", "-L", "{0}:localhost:{0}".format(host_port)]
    for process in psutil.process_iter():
        try:
            if process.name().endswith('ssh'):
                if process.cmdline()[-len(ssh_args):] == ssh_args:
                    process.kill()
        except psutil.NoSuchProcess:
            pass

Obviously, the process filtering is more rigorous in the Python version.