Bridging interfaces

[Simon Timms]

Thanks for your help Chris, I ended up rebooting the router since I wasn't
sure what manner of nonsense I'd put in and everything is working.

On 9/29/07, Christopher Cowart <ccowart at rescomp.berkeley.edu> wrote:
>
> On Sat, Sep 29, 2007 at 09:49:36PM -0600, Simon Timms wrote:
> > That makes a lot of sense, but I suppose I still don't understand why
> this
> > isn't working.  The handbook section on routing is pretty basic and it
> seems
> > to come down to setting net.inet.ip.forwarding to 1 if you want to route
> > packets between interfaces on a dual-homed host.  I'm able to reach
> hosts on
> > both subnets from the router and my routing table looks like:
> >
> > Internet:
> > Destination        Gateway              Flags       Refs      Use  Netif
> > Expire
> > default               wireless               UGS         0          9905
> > sis0
> > localhost           localhost              UH            0           134
> > lo0
> > 192.168.1          link#1                  UC            0
> 0
> > sis0
> > orinoco              00:d0:09:f8:f7:5a  UHLW       1
> 268    lo0
> > 192.168.1.255    ff:ff:ff:ff:ff:ff            UHLWb     1             87
> > sis0
> > 192.168.2          link#2                  UC            0             0
> > rl0
> > 192.168.2.255    ff:ff:ff:ff:ff:ff            UHLWb     1            87
> > rl0
>
> Are your 192.168.2/24 machines configured to use 192.168.2.2 as their
> default router? They don't know where 192.168.1.2 is, because they
> don't see it as being on the same link. The subnet mask is used to
> determine this kind of reachability.
>
> You could probably use 192.168.1.2 as your default router, as long as
> you created a static route `route add 192.168.1/24 192.168.2.2', telling
> the system that to get to 192.168.1/24, the next-hop is 192.168.2.2.
> This seems needlessly complex when you can just configure 192.168.2.2 as
> your default router and skip the static route configuration all
> together.
>
> Regardless, bridging isn't going to help unless the host and the default
> router have the same subnet configurations.
>
> --
> Chris Cowart
> Lead Systems Administrator
> Network & Infrastructure Services, RSSP-IT
> UC Berkeley
>
>