How do I associate an open port with a running program?
eg: what is listening on port 22?
# lsof -i :22
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
sshd 1318 root 3u IPv4 2444 TCP *:ssh (LISTEN)
sshd 7665 root 4u IPv4 166534123 TCP netbackup:ssh->router:918 (ESTABLISHED)
sshd 19710 root 4u IPv4 554877146 TCP netbackup:ssh->router:853 (ESTABLISHED)
eg: what is listening on port smpt (the mail port)?
# lsof -i :smtp
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
sendmail 25860 root 4u IPv4 66767220 TCP *:smtp (LISTEN)
New hotness: ss
# ss -tln
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 4096 127.0.0.1:199 0.0.0.0:*
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 128 [::]:22 [::]:*
where:
- -l means listen
- -t means tcp ports
- -n means show numbers rather than names