The ss (socket statistics) command provides information by displaying details on socket activity. Some command line switch examples would be:
ss -ta dumps all TCP socket
ss -ua dumps all UDP sockets
ss -wa dumps all RAW sockets
ss -xa dumps all UNIX sockets
ss -4a dumps all IPV4 sockets
ss -6a dumps all IPV6 sockets
ss –lt displays only listening sockets
ss-ltn displays the same data with port numbers
ss-t displays established TCP connections
https://www.networkworld.com/article/3327557/linux/using-ss-to-examine-network-connections.html