How to modify remote ports in CentOS 7 and 8
1. SSH remote login to the server
2. Enter (change port policy, allow firewall to pass policy, restart SSH):
(e.g.: port 55022)
sed -i 's/#Port 22/Port 55022/' /etc/ssh/sshd_config
sed -i 's/^Port.*/Port 55022/' /etc/ssh/sshd_config
firewall-cmd --zone=public --add-port=55022/tcp --permanent
firewall-cmd --reload
systemctl restart sshd
3. Log back in to SSH
4. CentOS7 and 8 port modifications are complete
