CentOS firewall configuration and shutdown

When using the CentOS operating system, the firewall configuration is very important, he is concerned about the safety of our computer. Once when the ORACLE database was installed under the CentOS operating system, it was shown that the EM installation failed because of the network port, so it was intended to shut down the firewall first. Ran into a firewall configuration instructions, I think it's not bad.
I. Execute the "Setup" command to start the text mode configuration Utility
Select firewall configuration in the Select a tool, then select the Run Tool button, the firewall configuration interface appears, the security level is set to Disabled, and then select OK.
Or we can use the command on the CentOS operating system:
#/sbin/iptables-i input-p tcp–dport 80-j ACCEPT
#/sbin/iptables-i input-p tcp–dport 22-j ACCEPT
#/etc/rc.d/init.d/iptables Save
Two. Reboot the computer.
1.CentOS operating system firewall has opened 80 and 22 ports by default
2. You should also not reboot your computer here:
#/etc/init.d/iptables restart
Firewall shutdown, turn off its services:
3. View firewall information:
#/etc/init.d/iptables status
4. Shut down the Firewall service:
#/etc/init.d/iptables stop
Three. Permanently shut down the firewall
We can also permanently shut down the firewall, but I don't recommend it. Permanently shutting down a firewall can do this:
#chkconfig –level iptables off
can also be directly modified
/etc/sysconfig/iptables
Add a
-A rh-firewall-1-input-m state–state new-m tcp-p tcp–dport 80-j ACCEPT
In this way, we've covered how to centos the operating system firewall configuration and shutdown steps.