I am looking to optimise my iBGP setup. Looking for some advice from those who have been using iBGP for a while.
I have a standard tree topology network.
Core>Tower1>Tower2,3,4 and so on
Core 10.0.0.0/24
Tower1 10.0.1.0/24
Tower2 10.0.2.0/24
Tower3 10.0.3.0/24
Core <bgp> Tower1 (tower 1 is a main distribution point to other towers)
Tower1 <bgp> Tower2
Tower1 <bgp> Tower3
Tower1 <bgp> Tower4
My questions are:
Should I continue to use a single ASN for all bgp peers? currently using '1'
At Tower1, should I use a single instance to both connect to Core and to Towers 2,3,4, or should I have an 'upstream' instance and a 'downstream', or even a different instance for each tower I connect to?
For route filters, should I be doing accepts and only allowing specific networks through? Or should I be letting anything through and disguarding certain networks?
Finally, when to use route-reflect. Just at Tower1 so that Towers2,3, and 4 can get those routes?
Thanks for any help in advance.