2 Internet Connection Routing Question
 

Hi all,

first post (as you can see), was pointed here by a user on another forum. I hate to say it, but I'm pretty new to Linux and so info I've found on what I'm trying to do is way over my head...

Basically, me and 3 mates are moving into a house very close to our university campus next year, and as such will be able to pick up the uni wireless network (with a bit of trickery involving a Pringles can), which will be used for downloading large files (very fast net connection) and accessing things that can only be accessed on the internal network.

However, we're also going to have a 1MBit ADSL connection for day-to-day surfing and running things that aren't allowed on the uni network, e.g. FTP/web servers, P2P etc.

Basically, we'll have the ADSL connection coming in and going to an ADSL router, which we'll have all our PCs connected to. Also connected to the router will be a Linux box (running RH 9) which will have two NICs in it - one wired to connect it to the home network, and one wireless to connect to the uni network. I do have a diagram of this, but unfortunately I'm not allowed to post a link to it (less than 5 posts).

Now, I've been told that by running Apache as a proxy server on the Linux box, and somehow implementing NAT and IPChains, that we can enter the internal IP address of the Linux box in a browser, and be presented with some kind of interface that will then allow us to browse the net, download stuff to our individual machines etc. via the wireless connection as opposed to our ADSL line.

Basically, my question is: where do I start? I've never used Apache, NAT or IPChains before and could really do with some kind of basic step guide on how to set this up! What I need to install, what order to do things in, useful links, etc. etc. Once I know where to start I can then ask more specific questions, but if any of you could help me out with this I'd really appreciate it!

Cheers,

Andy

If I'm following all this correctly, you'll want to set the Linux machine's default gateway to the router on the UNI network and then set up Squid and set your browsers to use it as needed.

Don't use Apache as a proxy. It'll wolk, but that's not what it was designed for.

I had heard Squid mentioned, so if that's a better way then I'll do it that way. The main problem I'm finding here is that it's not only certain predefined times like connecting to certain IPs that we'll want to use the uni connection, it could be for anything. So we need some kind of interface to ensure that when we browse to the Linux box we're actually using then browsing the net through the uni connection, not our ADSL line. This is kinda hard to explain, but we want to enter the Linux box's IP in our browsers, but we then need another page or something running on that to type in the address of the resource we want to access on the net, if you get me?

Cheers,

Andy

I don't think you're getting me.

If you set the linux box's default gateway to the UNI router, *everything* that is not on one of it's two local NICs will go out through the UNI router. Thus, any time you use the proxy on the linux machine, it will go out through the UNI connection.

If you want to use the UNI, connect via the proxy. If you don't, don't.

Ah, sorry, I was having a bit of a stupid moment there. OK, so would someone mind giving me a basic howto on setting up Squid? Where to download, how to install and configure?

Andy

http://www.google.com/search?q=squid+setup

I'm thinking of two possible solutions, one would be to set up some firewall rules so certain traffic goes through the campus net and other traffic goes through the DSL (such as ftp) and the other would be to make everything go through the campus network and then set up a proxy server that uses the DSL that you can switch to when needed.

The firewall is probably best set up using programs like http://www.shorewall.net/ and this would be something you have to set up in either case. The proxy is called squid, as was mentioned above, and look at the top of this post for more info there, remember search engines are your friend.