check port in centos 7 code example

Example 1: show port list in centos

# netstat -tulnp

Example 2: centos 7 port open

firewall-cmd --zone=public --add-port=55555/tcp --permanent
firewall-cmd --reload

Example 3: netstat centos ports

sudo ss -lntu

sudo netstat -ltup
sudo netstat -tulnp