[dns-operations] Monitoring anycast nodes for automatic route withdrawal

[David Ulevitch]

On Wed, Aug 4, 2010 at 2:29 PM, Joe Abley <jabley at hopcount.ca> wrote:
>
> Another way of doing this is to clone a loopback interface (e.g. ifconfig lo1 create) and bind the anycast service addresses to that. That loopback can then be ifconfig'd up/down to trigger the appropriate routing protocol action.
>

I would strongly recommend this course of action for a variety of
reasons above and beyond what Joe said. Having your service bound to a
loopback provides a number of benefits and provides a lot of
flexibility and we've never encountered a limitation.

Additionally, throw a unicast IP on the service powered by the same
daemon and monitor the heck out of that with DNS checks, too.  That
helps cover nearly all non-anycast-related variables.