[dns-wg] RIPE's MNAME recommendation

Hello dns-wg list!

SUMMARY:
In short, in a SOA RR of ours we have an MNAME that corresponds to a
primary master server which has a private IP address.  This is causing
problems with many RIPE member registrars.

PROBLEM:
Using the language described in Section 2.1 of [RFC 1996], we have a
primary master DNS server and two slave DNS servers.  The primary
master has a private [RFC 1918] IP address and the Slaves have public
IP address, are named in the NS RRs for the zone and use zone transfer
to recieve the zone from the primary master.  Furthermore, in
accordance with [RFC 1996], [RPC 1035] and [RIPE1] I have named the
primary master as the original/primary source of the data for the
zone.  Here is an example zone file from what I'm talking about:

     example.com.  3600  SOA  dns.private.example.com. hostmaster.example.com. (
                          1999022301   ; serial YYYYMMDDnn
                          86400        ; refresh (  24 hours)
                          7200         ; retry   (   2 hours)
                          3600000      ; expire  (1000 hours)
                          172800 )     ; minimum (   2 days)
                 NS slave1.example.com.
                 NS slave2.example.com.
     slave1      A  {public-ip}
     slave2      A  {public-ip}
     dns.private A  10.11.12.13

So far so good.  Our zone appears to be fully RFC compliant.  However,
the problem arises when I try to transfer, say, the ownership of
a ".de" zone using DENIC, because [RIPE1] additionally recommends
that this be a valid address of the primary master, "valid" being the
key word here.  This is a problem, because many RIPE member registrars
are indeed enforcing this policy.

I gather, however, from more recent messages from Mr. Koch (who authored
[RIPE1]), that the "MNAME field need not be part of the NS RRSet and
need not be accessible." [ICANN-FORUM].  BTW, to my knowledge this
is also neither enforced by IANA nor ICANN.

Is it possible that RIPE could consider relaxing this "recommendation"
that causes problems for RFC compliant zones?  How do you, the DNS
community, feel about this?

Thank you for your attention in this matter.

With kindest regards,

Paul Herman

Network Architect
cleverbrige AG
www.cleverbridge.com


REFERENCES:
----------
[RFC 1035]    Mockapetris,P., "Domain Names - Implementation and
               Specification", RFC 1035, STD 13, November 1987

[RFC 1918]    Y. Rekhter, B. Moskowitz, D. Karrenberg, G. J. de Groot,
               E. Lear. "Address Allocation for Private Internets."
               February 1996

[RFC 1996]    Vixie,P., "A Mechanism for  Prompt  Notification  of
               Zone Changes (DNS NOTIFY)", RFC 1996, August 1996

[ICANN-FORUM] http://forum.icann.org/lists/iana-del-data-comments/msg00004.html

[RIPE1]       Koch,P., "Recommendations for DNS SOA Values", ripe-203,
               http://www.ripe.net/ripe/docs/ripe-203.html , June 1999