Built-in firewall of Redhat 7.1 ???

[HaoDr]

Hi everybody,

I have just installed Redhat 7.1 on my PC, while I was choosing options to customize Redhat configuration on my box, I found it has a option to setup a built-in firewall in my computer ( high, medium and no rule option ).

So I would like to know about this firewwall's mechanism, I mean what is automatically set up on my system ( what programs is used and configure them ) ?

And how do I have to configure the same work my self instead of this utility implementing it?. Could you tell step by step to implement this task.

Any help would be highly appreciated.

Hao Dr

 

[RhythmAce]

Hi HaoDr,

If you installed RedHat as a workstation or are just using it to get the feel of linux, then you really don't need a firewall. If you plan to use it as a server, then you might try 'Lokkit' which comes packaged with RedHat. This lets you choose if you want web server, ftp, telnet or mail access and what level of security you want for each of them. There are other firewall programs that you can use but I mentioned Lokkit because it comes with RedHat and it will give you an idea of what a firewall is and how it works.

 

[ifincham]

Hi,

The redhat firewall (lokkit) comprises a set of ipchains rules which are created by the gui utilities, i.e. 'lokkit' and 'gnome-lokkit'. This firewall is fairly simple and doesn't have much documentation - this is the home page -->

http://www.linux.org.uk/apps/lokkit.shtml

.

The rules written by lokkit are run under the sysv init process by the service 'ipchains'. In other words, it would be active at the runlevels shown by '/sbin/chkconfig --list ipchains'.

For any serious / corporate firewall you would be much better off writing your own and preferably using iptables instead of ipchains. Unfortunately, most of the documentation out there is still ipchains oriented. Redhat's own info is here -->

http://www.redhat.com/support/resources/networking/firewall.html

.

Once you have created a iptables/ipchains script you have to choose how to activate it. The simplest is to call your script from /etc/rc.d/rc.local which is run at the end of the boot sequence. More sophisticated would be to create a sysv init compliant script and place it in /etc/rc.d/init.d . Then you use the runlevel editor tools to create the symbolic links that will start/kill the service at the required runlevels. Redhat have a '/etc/rc.d/init.d/local' script that you can use or create one of your own. Turn on with something like '/sbin/chkconfig --level 2345 local on'

Hope this helps