Authoritative record

[Kevin Darcy]

Dave Comcast wrote:

> What determines that a dns is authoritative to a domain?  Any examples?

A nameserver is authoritative for a zone if it a) is an origin of zone
data and b) replicates all zone data which it does _not_ originate from
one or more other authoritative servers and c) suffers no operational
problems (e.g. failed validation or zone data, failed replication) would
prevent the nameserver from claiming authority for the zone.

Note that the above is a very generic definition which even tries to
accommodate so-called "multi-master DNS", which is not supported by BIND.
In BIND-specific terms, a nameserver is authoritative for a zone if it is
defined as "type master" and has successfully loaded all of the zone data
(typically from a zone file), or if it is defined as "type slave" and a
successful zone transfer has occurred more recently than the
EXPIRE interval for the zone (EXPIRE is specified in one of the fields of
the zone's SOA record).


- Kevin