Finding listening ports on any operating system
ss - the new netstat
# show number listening process
ss -nlp | grep -e ^tcp -e ^tcp6 -e ^udp -e ^udp6Output
udp UNCONN 0 0 127.0.0.53%lo:53 0.0.0.0:* users:(("systemd-resolve",pid=1985,fd=13))
udp UNCONN 0 0 10.32.57.255:137 0.0.0.0:* users:(("nmbd",pid=2033,fd=16))
udp UNCONN 0 0 10.32.57.3:137 0.0.0.0:* users:(("nmbd",pid=2033,fd=15))
udp UNCONN 0 0 0.0.0.0:137 0.0.0.0:* users:(("nmbd",pid=2033,fd=13))
udp UNCONN 0 0 10.32.57.255:138 0.0.0.0:* users:(("nmbd",pid=2033,fd=18))
udp UNCONN 0 0 10.32.57.3:138 0.0.0.0:* users:(("nmbd",pid=2033,fd=17))
udp UNCONN 0 0 0.0.0.0:138 0.0.0.0:* users:(("nmbd",pid=2033,fd=14))
udp UNCONN 0 0 0.0.0.0:44900 0.0.0.0:* users:(("avahi-daemon",pid=2020,fd=14))
udp UNCONN 0 0 0.0.0.0:5353 0.0.0.0:* users:(("avahi-daemon",pid=2020,fd=12))
udp UNCONN 0 0 [::]:33933 [::]:* users:(("avahi-daemon",pid=2020,fd=15))
udp UNCONN 0 0 [::]:5353 [::]:* users:(("avahi-daemon",pid=2020,fd=13))
tcp LISTEN 0 4096 127.0.0.53%lo:53 0.0.0.0:* users:(("systemd-resolve",pid=1985,fd=14))
tcp LISTEN 0 128 0.0.0.0:22 0.0.0.0:* users:(("sshd",pid=2231,fd=3))
tcp LISTEN 0 10 127.0.0.1:25 0.0.0.0:* users:(("sendmail-mta",pid=2872,fd=4))
tcp LISTEN 0 50 0.0.0.0:445 0.0.0.0:* users:(("smbd",pid=2438,fd=46))
tcp LISTEN 0 16 127.0.0.1:3493 0.0.0.0:* users:(("upsd",pid=2410,fd=4))
tcp LISTEN 0 80 127.0.0.1:3306 0.0.0.0:* users:(("mariadbd",pid=2367,fd=28))
tcp LISTEN 0 10 127.0.0.1:587 0.0.0.0:* users:(("sendmail-mta",pid=2872,fd=5))
tcp LISTEN 0 50 0.0.0.0:139 0.0.0.0:* users:(("smbd",pid=2438,fd=47))
tcp LISTEN 0 128 [::]:22 [::]:* users:(("sshd",pid=2231,fd=4))
tcp LISTEN 0 50 [::]:445 [::]:* users:(("smbd",pid=2438,fd=44))
tcp LISTEN 0 16 [::1]:3493 [::]:* users:(("upsd",pid=2410,fd=5))
tcp LISTEN 0 50 [::]:139 [::]:* users:(("smbd",pid=2438,fd=45))#end