8 Aug
2025
8 Aug
'25
9:23 a.m.
On Fri, 8 Aug 2025 at 12:19, Måns Nilsson via NANOG <nanog@lists.nanog.org> wrote:
my one advice on anycast is to make _certain_ that the routing reflects service availability on individual nodes -- i.e a node that can't answer queries MUST stop advertising the resolver /128 (or /32 if you have that).
If you do this in a single ASN, where you can guarantee preferences are honored, then instead of pulling advertisement, deprefer it. Eventually you will manage to cause an issue, where all advertisements are falsely pulled. Same strategy works in any domain where you are testing if something works, like default route by pinging 8.8.8.8, don't pull, depref. -- ++ytti