Need Linux machine to route / packet forward

[rdd]

Hello --

I post here a broken man. I've spent the entire day trying to reconfigure my (modest) home network (way to spend a day off, eh ), and am near to giving up for the night. Here is what I'm trying to accomplish:

Cable modem --> Linux machine (web server, Snort, Ethereal) --> WAP + 4-port switch --> internal network computers (3)

Now, my (main) problem lies in getting this Linux box to route/forward traffic on to the WAP and WAP-connected internal machines (I think). It has two NICs (obviously), both of which are functioning. I have eth0 connected to the cable modem, w/ dhcp addy. eth1 I've statically assigned a private IP. /etc/sysctl.conf net.ipv4.ip_forward = 1. WAP and the internal network are functioning fine amongst themselves. The Linux machine can access the internet (thank god - otherwise I wouldn't know what to do ). I *cannot* ping from Linux into the internal network, or vice versa. Firewalls have been (temporarily) turned off on all machines.

Two things come to my mind:
1) for some reason, routes that I have added for eth1 (to WAP and internal network) in the Network Configuration applet do not show up with a 'route' command. Strange, no? Is this a problem? Should I manually add them from the command line? (I would have already, but the syntax perplexes me)
2) Do I need additional "routing" software for a setup as simple as this? This hadn't even occurred to me as a possibility until I did some browsing around the boards tonight. Freesco, Smoothwall, etc....do I need one of these?? I am not opposed; I just hadn't thought a simple forwarding arrangement would require it. If I do need somethingalong these lines, any recommendations between these two, or for others? Obviously, I am not an expert at Linux/Networking/Routing, but I would like to learn the most "realistic" package, if not too difficult.

Well, that is it for now, I guess. Sorry for being so longwinded. Any helpful replies are greatly appreciated. I'd be glad to provide more detail as needed also.

Thank you kindly.

[Compunuts]

Don't know what distro you are using ..

But on my Debian Unstable with Shorewall as my firewall, the shrewall took care of all that forwarding, Masq and NAT stuff.

What firewall are you using?

Also, your kernel need to have those functions built in but if you are using modern Linux distro, then chances are pretty good that it had already been included.

HTH

[mcdougrs]

Ok I have a couple of question for you.

What kind of switch do you have?

Is a switch and a router the same thing? If so my assumption would be that most routers/switches are set up to get an IP via DHCP (at least mine was). So you might need to get into the switches admin interface and set it to a static IP (if you aren't running DHCP on your linux router box that is) or tell it where to grab its DHCP address from.

Other than that I have no idea so you may want to try out Shorewall or one of the other firewalling packages/scripts.

HTH

[rdd]

( post #4)

Hello all --

thanks for the replies. I've actually given up, and gone back, "tail between legs", to my previous network config (with a few twists). I think I bit off too much this time around -- I'm going to spend a few months reading up on routing, linux firewalls, etc. before I try again. In the meantime, it is much safer for me to keep my linux box back behind my WAP firewall, especially since I have not yet mastered IPTables, or, for that matter, keeping my redhat box patched. ; )

Cheers,

[Compunuts]

Unless your Red Hat is the professional version with your work buying the license, you will be much better off ( security wise and update wise ) using Fedora Project ( currently ore 2 ). It's community maintained version of Red Hat desktop Linux.