I do Anycast for much much smaller. It's great to reboot one server and have the other take all of the load. 0 customer interruption, not even a single DNS query lost. On Fri, Aug 8, 2025, 12:21 PM William Herrin via NANOG < nanog@lists.nanog.org> wrote:
On Fri, Aug 8, 2025 at 2:17 AM Måns Nilsson via NANOG <nanog@lists.nanog.org> wrote:
anycast unbound, preferably on something more mature than Linux, so like FreeBSD or OpenBSD.
You don't need anycast DNS for 30k users. Stay away from anycast unless you really, really, really know what you're doing.
DNS is also TCP and no commodity DNS software environment implements an anycast TCP stack, only the normal unicast stack. Route splitting shows up in the most unexpected places and it won't just give you a bad day, it'll give you a bad month with intractable and seemingly (but not really) intermittent problems that are challenging to nail down.
Regards, Bill Herrin
-- William Herrin bill@herrin.us https://bill.herrin.us/ _______________________________________________ NANOG mailing list
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