Firewalld & Iptables
The most common network filtering programs is iptables. In latest Red Hat Enterprise and other linux based Operating system another firewall is available named as Firewalld . Iptables was the main method for network packet filtering program in earlier or old Red Hat and CentOS versions.
In latest CentOs / RHEL 7 both system based OS, so we will use system related command to enable,disable and stop firewall and iptables.
Disable Firewalld :
Here we are going to disable and stop default firewall firewalld .
# systemctl stop firewalld
# systemctl disable firewalld
In latest version of RHEL / CentOs, both iptables and firewalld can be available for use, then system may have conflict services installed . For prevention of an administrator from accidentally starting a service, a service may be masked.Masking will prevent if the services is started , nothing will happen.
# systemctl mask firewalld
Install and Configure Iptables :
Here we are going to fresh install iptables service, may be in your server it already installed. Please check other wise install through below command.
# yum -y install iptables-services
Create Iptables files :
Run below command for create a blank or null files for iptables.
# touch /etc/sysconfig/iptables
If you use ip6tables services , then run the below command.
# touch /etc/sysconfig/ip6tables
To check and verify service will starts at boot :
# systemctl enable iptables
If you are using ip6tables, please run below command otherwise you can left or skip below command.
# systemctl enable ip6tables
Now lets start the iptables services.
# systemctl start iptables
For ip6tables services, use below command.
# systemctl start ip6tables
Now we have run the iptables services and stop and disable firewalld services.