netstat can be installed from net-tools package. The netstat is often used to display open ports, packet details and network usage.
// Show all listening TCP ports # netstat -alt
// Show routing table # netstat -r
// Show multicast group membership information # netstat -g
// List all network interfaces with specific properties # netstat -i
// List summary of statistics for each protocol # netstat -s
// List all TCP connections # netstat -a --tcp
