Address already in use

If you want to see which process is listening on a certain port, use lsof. For example, looking for what's running on 9292 is:

1

  lsof -i :9292

COMMAND   PID    USER   FD   TYPE             DEVICE SIZE/OFF NODE NAME
ruby    27467 wschenk   13u  IPv4 0x8cf71cd7f78517e3      0t0  TCP localhost:armtechdaemon (LISTEN)
ruby    27467 wschenk   20u  IPv6 0x8cf71cdcbf525e93      0t0  TCP localhost:armtechdaemon (LISTEN)

And then you can kill it with

1

  kill 27467