On Sun, 2010-05-16 at 11:02 +0100, Martin A. Brooks wrote: > What's an RR?
The correct term for a Resource Record, ie. a primitive in a DNS zone.
> Assuming you mean "reverse record", surely a "PTR RR" is just an A record
> and a "A RR" is actually just a PTR?
No. An A RR is the proper name for an "A record", PTR RR "PTR record"
and so on.
> The concept of a "MX RR" is pointless, as an MX is just a special case of
> an A record.
No it isn't. An MX RR has a metric (weight) associated with it, as well
as name and data. An A RR has only name and data. Also of note is that
an MX RR cannot have an IP address in the data field (not that it stops
people putting them in).