I really really wish there were a couple of well-known and globally respected communities which you could set to say either "this is a route of last resort" or "this is my preferred route". I feel like it would avoid many of us doing exactly what you're about to do which is pollute the routing tables with extra, more specific routes to do basic traffic engineering. (Resulting in 3 routes where one would do). I'm not talking fine level control here, just being able to say "hey this route is better than nothing, but not much" or "treat this as backup". I understand the resistance to honoring various route engineering tactics, but being able to effectively do the exact same thing that announcing more specifics does without having to resort to announcing more specifics would be a good thing as far as the global bgp table size goes. On Mon, Jan 22, 2024, 1:16 PM William Herrin <bill@herrin.us> wrote:
On Mon, Jan 22, 2024 at 5:23 AM Jon Lewis <jlewis@lewis.org> wrote:
You may be limited to seeing if your backup providers have community controls that would let you tell them "don't share with Centurylink"
As I already explained, neither the primary nor any of the backup providers directly peer with Centurylink, thus have no communities for controlling announcements to Centurylink.
I hate to litter the table with a batch of more-specifics that only originate from the short, preferred link but I'm not hearing any practical alternatives. Treating my distant links as equivalent even though I told you with prepends that they are not leaves me with few knobs I can turn.
Regards, Bill Herrin
-- William Herrin bill@herrin.us https://bill.herrin.us/