Register.com DNS hosting issues
randy at psg.com
Sat Apr 4 17:41:12 CDT 2009
> IMHO, fate-sharing as a strategy for increasing availability is
> somewhat underrated.
from rfc 2182
3.3. A Myth Exploded
An argument is occasionally made that there is no need for the domain
name servers for a domain to be accessible if the hosts in the domain
are unreachable. This argument is fallacious.
+ Clients react differently to inability to resolve than inability
to connect, and reactions to the former are not always as
+ If the zone is resolvable yet the particular name is not, then a
client can discard the transaction rather than retrying and
creating undesirable load on the network.
+ While positive DNS results are usually cached, the lack of a
result is not cached. Thus, unnecessary inability to resolve
creates an undesirable load on the net.
+ All names in the zone may not resolve to addresses within the
detached network. This becomes more likely over time. Thus a
basic assumption of the myth often becomes untrue.
It is important that there be nameservers able to be queried,
available always, for all forward zones.
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