RE: [TCLUG:8342] Multiple Ethernet

["Eric Hillman" <ehillman@cccu.com>]

> Well, let me see...in the netconfig(redhat 6.0) panel, ip
> forwarding is checked.
>
> As for everything else, this machine is (going to be) the gateway machine,
> unless I'm really confused on things, which is likely the case.  Right now
> all I have is an ISDN router (Ascend Pipeline 75, I believe) that does our
> gatewaying...
>
> My plan was to plug a hub to the router (so that a few boxes
> could be outside the firewall,
> should I want that later.) and off that hub, have this firewall
> box be a bridge between the office
> and the router.  I assumed that would mean that I would make the
> firewall box also become
> a gateway.
>
> Am I wrong?


	I'm a little confused here -- what you're saying here makes sense, but
doesn't seem to jibe with what you described earlier.

	So, instead of trying to understand what you're doing, I'll tell you what
I'd do (or rather, have done -- this is the way my home and work networks
are both set up...)

      Your router should be connected to your hub, and then the hub
connected to eth0 (your 1st ethernet card).  Eth0 should be configured to be
in the same IP domain as the router. (This is another thing that confused me
about your description -- you say your ISP assigned you 192.168.6.xxx?
That's not a routable IP -- that's one of the reserved Class C addresses for
internal network use.  If this is the case, your router must *already* be
doing IP masquerading.)

     Your second network card, eth1, should be plugged into a seperate hub
or switch, and your internal network run from there.  eth1 should be on a
different domain than eth0 -- 192.168.100.xxx or something.  That domain
should be the one you use for all internal machines.  Then all you have to
do is enable ip forwarding and masquerading (see manpages on ipchains or
ipfwadm, depending on your version of Linux), and you should be ready to
rock.