Centos and Redhat EL firewall port opening

http://ask.xmodulo.com/open-port-firewall-centos-rhel.html

Centos 7
To open up a new port (e.g., TCP/80) permanently, use these commands.

$ sudo firewall-cmd --zone=public --add-port=80/tcp --permanent
$ sudo firewall-cmd --reload 

 

Check the updated rules with:

$ firewall-cmd --list-all

 

Centos 6, iptables

Use iptables command to open up a new TCP/UDP port in the firewall. To save the updated rule permanently, you need the second command.

$ sudo iptables -I INPUT -p tcp -m tcp --dport 80 -j ACCEPT
$ sudo service iptables save 

 

Start / Stop / disable firewall completely

 

https://linuxconfig.org/how-to-stop-start-and-disable-enable-firewall-on-redhat-7-linux-system

 

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