DNS anycasting - multiple DNS servers on same subnet Vs registrar/registry policies

Mon May 28 19:18:32 UTC 2012

Anurag,

On May 28, 2012, at 11:51 AM, Anurag Bhatia wrote:
> I know few registry/registrars
> which do not accept both (or all) name servers of domain name on same
> subnet. They demand at least 1 DNS server should be on different subnet for
> failover reasons (old thoughts).

IMHO appropriately so.  The fact that anycast allows for multiple (potentially) geographically distributed machines to respond to DNS queries does not remove the value of having multiple prefixes for DNS servers. Single points of failure are generally bad. Imagine the scenario where someone makes a booboo and accidentally filters your single anycast prefix...

Regards,
-drc