You can use the following commands to start/restart/stop iptables on your Linux server:

To start iptables:
service iptables start

To stop iptables:
service iptables stop

To restart iptables:
service iptables restart

You can determine whether iptables is running or not using following command:

service iptables status

You can also configured iptables to start automatically on boot. You will need to use chkconfig command to turn it on:

chkconfig iptables on

To use above commands, you will need the root access of your server.

Kailash

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