Two interfaces on the same network

[Larry Brown]

---------                                       -----------------
| Linux | 192.168.2.1 --Wireless--> 192.168.2.2 | Wireless User |
---------                                       -----------------
192.168.1.1
    |
    |
  Wired
    |
    |
    V
192.168.1.2
--------------
| Wired User |
--------------

Sorry, my first ansi drawing.  Why can't you use this?  If the Linux box
is set up to route traffic between the networks,  Each machine can see
one another.  Each machine can access the html access on the Linux box. 
Or if you use a wireless node on the network, you could have wireless
users coming onto the 192.168.1 subnet and everyone can see everyone as
they will be on the same subnet for that scenario.  

When the ping is received by the Linux box when two nic's have the same
subnet, the OS receives the request for ping and looks at the routing
table for a route back to the sendor.  If the arp tables show his mac
address on the first card on that network (even though the ping came in
on the second card on that network), it will send the ping response on
that first card.  So the windows box can see a ping response coming
back, but it may be coming from an address other than the one it sent it
to in the first place and ignores it.  As far as I can tell this is how
these things were designed for TCP/IP.  M$ doesn't want multiple cards
on one box on the same subnet either.  The fact that your M$ box is
doing it is an oversight on their part.  I'm pretty sure they addressed
that in networking for the MSCE cert.


On Wed, 2004-06-09 at 14:22, Rodolfo J. Paiz wrote:
> At 12:08 6/9/2004, Al wrote:
> >I didn't set default gateway (if that's what you meant "default route")
> >
> >I just bring up two interfaces with:
> > >ifconfig eth0 172.20.1.30 netmask 255.255.255.0
> > >ifconfig eth1 172.20.1.31 netmask 255.255.255.0
> >
> >that's it. no more route or other commands.
> 
> So as root:
> 
> # ip addr show
> # ip route show
> # route -n
> 
> What do those commands show?
> 
> 
> -- 
> Rodolfo J. Paiz
> rpaiz at simpaticus.com
> http://www.simpaticus.com
>