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Re: The demon problem, ancestor matching, and match_subdomains=yes

2004-03-23 10:21:02
On Tue, Mar 23, 2004 at 10:14:57AM -0600, wayne wrote:

Wait a second, in what way are SOA records optional?  This is a new
one on me...

Yeah, it was news to me also when I read it in the BIND source.

RFC1035 says:

: 5.2. Use of master files to define zones
: 
: [snip]
:    2. Exactly one SOA RR should be present at the top of the zone.

I think the "optional SOA" record is like the "optional MX" record
thing.  They were both later creations and no sunset provision was
mandated.  Hence, we are stuck with both of them being optional until
such time as a sunset provision is created.

This RFC doesn't use "SHOULD" and "MUST" and the like.

I think the use of "should" should be read as "MUST" in this case.  The
record is not optional when I read this snippet of par. 3.3:
 "In particular, NS, SOA, CNAME, and PTR will be used in all classes,
  and have the same format in all classes."

Of course, a SOA record should be present for each zone, not for each
domain.

HTH
Alex