Do you want to disable Firewall on your linux system there are two ways,

Using setup command
Disable (stop) iptables

On this post we can disabled firewall  using setup command on Terminal,

# setup

After executing the command shows popup screen, the press  "Down or Up"  arrow key to choose the options,

Select " Firewall Configuration "  => " Run Tool "

By default the Firewall enabled on your system, to disabled it press "Space Bar" the star symbol will be  vanished, like below image.

Finally press "OK"

and then press "Yes"

Finally restart your system if you need it.
# init 6