markdown 在服务器上关闭和打开端口

Posted 2021-05-05

### login
`ssh [e-mail]`  


### change to superuser
`sudo su`  


### logout
`logout`  

## List Current Firewall Rules
`iptables -L`  

This command lists all the current firewall rules loaded into IPtables.


## Open a port in IPtables – CentOS 6
`iptables -I INPUT -p tcp -m tcp --dport 80 -j ACCEPT`  
`service iptables save`  


## Open a port in IPtables – CentOS 7
`firewall-cmd --zone=public --add-port=80/tcp --permanent`  
`firewall-cmd --reload`


## Close a port in IPtables – CentOS 6
`iptables -I INPUT -p tcp -m tcp --dport 80 -j REJECT`  
`service iptables save`  


## Close a port in IPtables – CentOS 7
`firewall-cmd --zone=public --remove-port=80/tcp`  
`firewall-cmd --runtime-to-permanent`  
`firewall-cmd --reload`