> BGP has no way to know that an internal network problem occurred. If
> someone mistakenly tripped over a network cable that disconnected DNS
> clusters from a router, how would the router know to drop anycast
> (Sure, you could run zebra on the cluster. But what about if the name
> server SEGVs? There's a lot of possible scenarios....)
ALmost there.. just make sure your zebra IGPs are redistributing to your BGP so
that a failure such as that knocks out the bgp too
Sorry no zebra. Perhaps I should run my TLDs
DNS service on my Juniper Routers. some expect/cron
work should provide the needed glue...
Now if I could just get cisco to add authoritative
DNS service to IOS, right up there with the HTTP, firewall,
content caching, and load-balancing cruft they have
added to their basic routing code... I could use
cisco too! (may still need some glue tho)
In case it was not clear, I think that multi-tasking
hardware might be the wrong choice. I want my routers
to route and not do apps work. For apps, I want them
to be single-app specific. DNS service on its own hardware,
NTP on its platform, HTTP outsourced to (vendor), etc.
This has impact on the design of anycast solutions.
Ultra has one model, ISC has another, and PCH uses
a third. The more generic content crowd has its favorites.
Then there are the "load-balancing" vendors who
cater to these folks. One size does not fit all.