centos 7 open ports

1. Check firewall status

systemctl status firewalld 或者 firewall-cmd --state

1. Whether temporarily turn off the firewall test is a port problem

systemctl stop firewalld

1. Open the firewall

systemctl start firewalld

1. Increase port

firewall-cmd --zone=public --add-port=80/tcp --permanent
firewall-cmd --zone=public --add-port=12345/tcp --permanent

1. Reload

firewall-cmd --reload