[c-nsp] BGP multihop between two sites

[Randy McAnally]

We have two sites advertising unique subnets via the same AS.  Since the
subnets originate from the same AS they apparently get dropped from the tables
at each site.  

Each site has at least 3 upstreams taking full tables from each with a 6509.  

Site a has a single border router with dual supervisors.

Site b actually has dual border routers.  Each router handles different
upstreams and trades routes via iBGP.

So I think I need to set up a multihop session between the sites.  

Right now, traffic between sites is taking the floating default route and
causes issues between sites when one of our BGP peers is down for whatever reason.

What are the things to look out for when setting up this multihop?  Are there
gotcha's to deal with given one site has dual active routers?

Can anyone provide me or point me to an example multihop config to work from?

--
Randy