Re: BGP and aggregation

[Stephen Griffin <stephen.griffin () rcn com>]

In the referenced message, Ralph Doncaster said:
> > BGP will discard any prefix with its own AS in the path, for loop
> > prevention. Hence, one half of the AS would still be unable to
> > reach the other half. This is why a partitioned AS is a failure
> > condition. A tunnel is a means to keep the AS nonpartitioned.
>
> I was thinking of doing iBGP over my transit connections (with a couple 
> of static routes so the iBGP works) AND over my inter-city circuit.  Any
> reason why this won't work?
>
> -Ralph

The loss of igp metric will make it untenable at best. Do it over a
GRE tunnel, with your regular igp (isis, ospf, eigrp, or shudder rip).

default routes have their own problems which only treat the symptoms
of a partitioned as, rather than the problem.