RE: bidirectional forwarding

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> Jason Opperisano schreef:
>
> > > PC1               R1           R2           R3           R4            PC2
> > > |---------------|   |-------|    |--------|   |--------|   |-----------|
> > > 192.168.10.2   .1  12.1    12.2 13.1     13.2 16.1    16.2 11.1       11.2
> > > e0             e0   e1     e0   e1        e0  e1       e0  e1          e0
> >
> > assuming:
> >
> >   default gw of pc1 is 10.1
> >   default gw of r1 is 12.2
> >
> >   default gw of pc2 is 11.1
> >   default gw of r4 is 16.1
> >
> > both r2 & r3 will need static routes telling them how to get to networks 10 and 11:
> >
> > on r2:
> >
> >   192.168.10.0/24 via 192.168.12.1
> >   192.168.11.0/24 via 192.168.13.2
>
> How cat r2 reach your 16-network? you will need to add a routing for
> that network to.

why does r2 need to know how to get to the 16 network?  IIRC--the OP never indicated an interest in a "fully-routed" environment.  as long as 10.2 can talk to 11.2 and vice versa--everyone's happy.  the transport networks are irrelevant to the solution and would only serve to distract from the real problem.

>
> Routingprotocols are designed for this kind of problem, to get this
> resolved
> automaticly. In this case you might look at zebra.

uh huh.  my personal opinion is that dynamic routing protocols on firewalls are a Bad Idea (tm), and should only be used when necessary (in networks with redundant paths that must be learned automatically).  the scenario above does not meet this criteria.  also, (again my opinion)--routing transport networks (i.e. networks that will never have traffic that sources from or is destined to them) is just a waste of time.  finally, i think if people took the time to understand how to statically route an environment before spewing "redistribute everything" statements all over their router configs--they might actually end up understanding what's going on.

not saying that the OP might not *want* a fully routed environment, but saying that these additional routes are *needed* is simply not correct, and will only serve to continue to confuse those that have a hard enough time understanding routing to begin with (not implying that i'm not in that group myself).  :-D

-j



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