Netstat is a utility for gathering network statistics. It comes preinstalled on most systems.

If missing, here’s how to install.

# Redhat, CentOS
yum install net-tools
# Debian, Ubuntu, Mint
apt install net-tools
# SLES, SUSE
zypper install net-tools

Here are some common and useful commands.

# show version
netstat -v
# show routing table
netstat -nr
# show network interface statistics
netstat -ai
# show network connections
netstat -ant
# show network services
netstat -tulpn