* [email protected] (Aaron Gould) [Thu 02 Mar 2017, 20:52 CET]:
Yes, thanks, I am going to do that. But, is there a middle ground
between being default only and full routes ? Like is it
advantageous for me to ask for partial routes (like their routes and
direct peers and default route) ? This way I don't have millions of
routes but I guess only a few hundred thousand or less? Let me know
please.
You should ask for full routes from all your providers + a default.
Then you write per-upstream import policies to permit or deny specific
subsets of the prefixes they announce to you. For example, you could
accept all prefixes from Cogent and your other upstreams tagged with a
BGP community indicating they're from customers, and accept default
from all except Cogent to take care of the rest of the traffic while
still pretty much sending traffic to downstream customers to their
respective upstream. (Or you can accept default from all but also
import networks with whom Cogent has no direct relationship from your
other upstreams; but that's less failsafe.)
Depending on what router hardware you have and what upstreams, you may
have to filter out additional prefixes to not overflow its FIB.
-- Niels.
