Re: [TCLUG:13179] Firewall!!! (again)

[Nate Carlson <natecars@real-time.com>]

On Tue, 1 Feb 2000, Brian Ackermann wrote:

> Woo!
> 
> Well, the good news is that with the help of a good many of you on this list,
> I've managed to learn enough to get my firewall up and running, more or less.
> We're still having some problems, though, and after working on it myself since
> 7pm last night (minus the 5 hours I let myself sleep) and getting nowhere, I
> thought I'd go to the source...
> 
> Heres a recap of my system.
> 
> Firewall Box: Three Nics, on subnets A, B, and C.
> Subnet A is the external interface...IE: internet
> Subnet B is the 'server' group
> Subnet C is the 'workstation' group
> 
> IPCHAINS:  Allow everything, for a little while longer...
> 
> As of last night, I've managed to get all the issues between A,B and A,C worked
> out. So each of the subgroups work with the internet just fine.
> 
> The problem I have is how to get Machines on B, and C talking to eachother.
> >From C, I can ping a number of the servers in the B group, but not all.  I'm not
> sure why.  TCP appears to be set up correctly on all of the machines.  I just
> don't know what the deal is...
> 
> Suggestions?
> 
> I need to get this up and running in a hurry, because in a few short minutes,
> folks are gonna be hollerin' about not getting their email.
> 
> Thanks...
> 
> Brian

You need to do ip forwarding between the two interfaces. Here's something
that should get you working:

ipchains -P forward ACCEPT

-- 
Nate Carlson <carlson@real-time.com>    | Phone : (612)943-8700
http://www.real-time.com                | Fax   : (612)943-8500