firewall help

[Lai Zit Seng]

On Sun, 29 May 2005, freejay wrote:

> Hi, currently our network (2.2.2.x/16) is connected to a gateway router
> (with an IP address of 2.2.2.1) and we do not have any internet connection.
> My boss told me that our network would be connecting to the internet soon,
> so I better build a firewall for this. The firewall we came up with is a 3
> interfaced linux box. One interface is connected to the internet, another to
> our network, and the last one to the gateway router. Here's the problem:

Where does your gateway router connect to? The rest of the company 
network?

> 1.) the firewall should be transparent enough between the gateway and our
> network that if we need to disconnect from the firewall we could connect
> directly to the gateway router.

Install a bridging firewall. If anything mucks up and you need to remove 
the firewall, nothing changes in as far as IP-level is concerned.

> 2.) Our current settings on both gateway and network is retained even if
> connected to the firewall. (e.g. the gateway of our PC's are still 2.2.2.1)
> Hope somebody can help.

That gateway router can still remain the default gateway for everyone on 
your network. But you'd need to configure it to correctly route out to the 
Internet :)

Regards,

.lzs
--
http://zitseng.com/