E.B. Dreger wrote:
TV> Date: Thu, 18 Sep 2003 13:01:18 -0400 (EDT) TV> From: Todd Vierling
TV> BGP doesn't know when a DNS server dies. Therein lies the TV> findamental problem of using anycast as an application TV> redundancy scheme.
But it can and should. Again, seeing if the process is running is easy; verifying correct functionality requires more work, but definitely is doable.
And, I might add, in the case of a highly complex anycast application, you will need to check not only for correctness, but for timeliness. And, again, in the case of a highly complex app such as an anycast DNS, you need to check several behind the scenes apps, such as maybe a db, the responsivness of your high avail partner server, the dns daemon, connectivity through two or more network paths, connectivity to master update servers, BGP on whatever boxes are providing BGP, etc, the list goes on. But again, that's just my opinion, I could be wrong. ;-)