Red Hat 5 Internet Firewall

k_oudom · 01-26-2010, 06:28 AM

I already have Linux Enterprise 5 system installed with some server packages such as Webmin, Active Directory, Web Server which also act as Internet gateway. Now I want to add firewall functionality to block clients ip accessing internet. Can anyone help and give me the tutorial?

Web31337 · 01-26-2010, 07:28 AM

sure, man iptables.
to get a tutorial, just google for it.

k_oudom · 01-26-2010, 08:55 AM

Can you show me what package I need to install? How to install and configure?

housemusic42 · 01-26-2010, 01:52 PM

iptables (your firewall software) in RHEL5 comes default.

from a command line run:

Code:

system-config-securitylevel

that should give you a good start

salasi · 01-26-2010, 03:49 PM

Quote:

Originally Posted by k_oudom

I already have Linux Enterprise 5 system installed with some server packages such as Webmin, Active Directory, Web Server which also act as Internet gateway.

You installed active directory on RHEL? OK.

Quote:

Now I want to add firewall functionality to block clients ip accessing internet.

May not be possible, depending on your network structure, which you haven't mentioned. Shouldn't be a problem to you, though.

For iptables, there is a lot of material online; for a manual try this.

k_oudom · 01-27-2010, 09:07 AM

The network structure is that there is only a way internet traffic go through is the server. So if the server can be use as firewall, that would be enough to block traffic. So i'm not talking about normal firewall which just protect the server.

k_oudom · 02-04-2010, 06:19 AM

Today, I find out that the server have iptables installed already. It use Webmin as control panel. Now I want to know about how to block outgoing traffic using Webmin - Linux Firewall. Can anyone give me an example on how to block an IP of a local computer to access internet? I see too many options in Webmin - Linux Firewall. The server has two interfaces, one is WAN, one is LAN.

k_oudom · 02-05-2010, 04:34 AM

IPTables Screenshot

EricTRA · 02-05-2010, 04:51 AM

Hello,

Have a look here.

Code:

http://www.cyberciti.biz/faq/how-do-i-block-an-ip-on-my-linux-server/

Kind regards,

Eric

k_oudom · 02-05-2010, 06:07 AM

Eric, I read topic you gave me. I'm not sure if they talk about blocking an ip to access to local network and server. My network structure has two interfaces but the topic does not include any interface. I don't want block an ip access LAN(ether0) but I want traffic to stop when they bound outside to internet via WAN(ether1). Hope you can understand my writing.

EricTRA · 02-05-2010, 10:09 AM

Hi,

I don't have a lot of experience using/configuring iptables, so let's hope someone else kicks in with an answer/solution/tip/howto/link.

Kind regards,

Eric

Smartpatrol · 02-05-2010, 11:11 PM

k_oudom · 02-05-2010, 11:26 PM

I think I want to use Webmin that already installed. Do you experience Webmin? Webmin - Linux Firewall

Smartpatrol · 02-06-2010, 09:43 PM

k_oudom · 02-07-2010, 01:40 AM

But It seem that iptables command did not take effect. I think webmin protect iptables from accessing. Can anyone just tell me how to configure using webmin web interface? Anyone ever use Webmin?