CentOS7 firewall and port related commands introduction

 [root@hu ~]# firewall-cmd --state
not running ---Not running [root@hu ~]# firewall-cmd --state
Running --- Running

 [root@hu ~]# systemctl status firewalld.service

 [root@hu ~]# systemctl start firewalld.service

 [root@hu ~]# systemctl stop firewalld.service

 #Add the --permanent parameter, restart the service to take effect and permanently take effect;
#If the --permanent parameter is not added, it will take effect immediately and will become invalid after the service is restarted;
[root@hu ~]# firewall-cmd --zone=public --add-port=8080/tcp --permanent
success
[root@hu ~]# firewall-cmd --zone=public --add-port=80/tcp --permanent
success
#Restart the service to make the open port take effect [root@hu ~]# firewall-cmd --reload
success
#4.1. Verify whether the newly opened port is effective. Yes means it is effective, and no means it is not invalid. [root@hu ~]# firewall-cmd --zone=public --query-port=8080/tcp
yes

 [root@hu ~]# firewall-cmd --zone=public --remove-port=8080/tcp --permanent

#Command to verify whether the removal is successful [root@hu ~]# firewall-cmd --zone=public --query-port=80/tcp
#Or check the ports currently open on the firewall [root@hu ~]# firewall-cmd --permanent --zone=public --list-ports
8081/tcp 3306/tcp 111/tcp 111/udp 2049/tcp 2049/udp 1001/tcp 1001/udp 1002/tcp 1002/udp 30001/tcp 30002/udp 80/tcp 8080/tcp
#Add multiple ports by configuring multiple --add-port parameters, for example:
[root@hu ~]# firewall-cmd --zone=public --add-port=80/tcp --add-port=8080/tcp --permanent

 [root@hu ~]# systemctl restart firewalld.service

 [root@hu ~]# firewall-cmd --reloadsuccess

 [root@hu ~]# systemctl enable firewalld.service
#Restart the machine and check the firewall status[root@hu ~]# reboot
..
..
..
[root@hu ~]# firewall-cmd --state
Running --- indicates that the boot is successful