How to view UDP and other protocol connections?
netstat is weak and can't show udp connections and most other protocols, use "ss" which is what netstat should have been:
The "-u" switch stands for udp, here's a list of other options:
Usage: ss [ OPTIONS ]
ss [ OPTIONS ] [ FILTER ]
-h, --help this message
-V, --version output version information
-n, --numeric don't resolve service names
-r, --resolve resolve host names
-a, --all display all sockets
-l, --listening display listening sockets
-o, --options show timer information
-e, --extended show detailed socket information
-m, --memory show socket memory usage
-p, --processes show process using socket
-i, --info show internal TCP information
-s, --summary show socket usage summary
-4, --ipv4 display only IP version 4 sockets
-6, --ipv6 display only IP version 6 sockets
-0, --packet display PACKET sockets
-t, --tcp display only TCP sockets
-u, --udp display only UDP sockets
-d, --dccp display only DCCP sockets
-w, --raw display only RAW sockets
-x, --unix display only Unix domain sockets
-f, --family=FAMILY display sockets of type FAMILY
-A, --query=QUERY
QUERY := {all|inet|tcp|udp|raw|unix|packet|netlink}[,QUERY]
-F, --filter=FILE read filter information from FILE
FILTER := [ state TCP-STATE ] [ EXPRESSION ]
ss -u
State Recv-Q Send-Q Local Address:Port Peer Address:Port
ESTAB 0 0 192.168.5.21:44862 156.154.70.1:domain
ESTAB 0 0 192.168.5.21:55120 208.67.222.222:domain
ESTAB 0 0 192.168.5.21:51548 208.67.222.222:domain
ESTAB 0 0 192.168.5.21:37629 156.154.70.1:domain
ESTAB 0 0 192.168.5.21:50728 208.67.222.222:domain