bridging two networks

[kbrill]

I have two networks in the office.

One is on a Linksys WRT54G and is attached to a DSL line. All of the desktop machines and fileservers are on this network. It has an address range of 192.0.0.x (someone else started that, but it works)

The other network is on a cisco router (controlled by SWB) and a T-1. It has our web servers and mail server on it. It's address range is 70.239.221.x

right now, for anyone to get their mail or FTP to the webservers the request goes out the DSL line and back in the T-1 line. Which works fine but is a bit sluggish sometimes.

Is there a way to bridge the two networks so that someone on the 192.x network could get a resource on the 70.239.221.x network WITHOUT involving the external internet devices? I cannot put any more network cards in the 70.239.221.x servers. I already tried simply tying the two switches together, didnt really expect it to work but had to try.

[gtmtnbiker98]

Yes, it is rather easy to accomplish; however, you have some severe security implications to consider prior to doing this. If the latency can't be lived with then you can install two NIC's on any Linux box and have that box act as a NAT router or stateful firewall.

Are there any underlying reasons for having a setup like this? I am assuming that both of these networks are at the same location, correct? If so, install a multi-homed server, place a suitable OS on it, and configure a multi-homed network with a DMZ, LAN, and WAN interface. This is easy to achieve and best left for a weekend setup. Need help? Post back.

[oldcpu]

I already tried simply tying the two switches together, didnt really expect it to work but had to try.

What sort of cable did you use? Did you try a cross over cable (and failing that try a regular ethernet cable)?

(I'm not saying a cross over cable would work, given you already have each network on the internet, but it is worth trying).

[kbrill]

Yes, it is rather easy to accomplish; however, you have some severe security implications to consider prior to doing this. If the latency can't be lived with then you can install two NIC's on any Linux box and have that box act as a NAT router or stateful firewall.

Can't put any more network cards in the servers but I might (if I can find one) be able to put a USB NIC cable in one.

Are there any underlying reasons for having a setup like this? I am assuming that both of these networks are at the same location, correct? If so, install a multi-homed server, place a suitable OS on it, and configure a multi-homed network with a DMZ, LAN, and WAN interface. This is easy to achieve and best left for a weekend setup. Need help? Post back.

This is what I wanted to do. I have several SUSE linux machines that have 2 NICs in them. But when I follow the how-tos it never works. I can't get the 192.x.x.x machines to send requests for the 70.239.221.x machines thru the SUSE machine. Pings just time out.

[gtmtnbiker98]

Setup a low-end machine with three NIC's, download and install IPCop along with the admin manuals. Follow the onscreen instructions and the setup will do the rest. I would recommend a DMZ, LAN, WAN setup and do away with one of those expensive ISP connections. You will save money while at the same time consolidating your network for reduced administration and increased performance.

Just remember, IPCop is a distro by itself and will install in less than fifteen minutes. It is rock solid and capable of IP aliasing for that server farm that maintains a public presence. Smoothwall is another alternative; however, you have to apply modifications to the default install in order to assign more than one IP address to a single NIC for NAT/PAT.