RFC Errata
RFC 1995, "Incremental Zone Transfer in DNS", August 1996
Note: This RFC has been updated by RFC 9103
Source of RFC: dnsind (int)
Errata ID: 3196
Status: Held for Document Update
Type: Technical
Publication Format(s) : TEXT
Reported By: Alfred Hoenes
Date Reported: 2012-04-18
Held for Document Update by: Brian Haberman
Section 2, pg.2 says:
If an IXFR query with the same or newer version number than that of the server is received, it is replied to with a single SOA record of | the server's current version, just as in AXFR. ^^^^^^^^^^^^^^^^^^ [...] Thus, a client should first make an IXFR query using UDP. If the query type is not recognized by the server, an AXFR (preceded by a | UDP SOA query) should be tried, ensuring backward compatibility. [...] ^^^^
It should say:
If an IXFR query with the same or newer version number than that of the server is received, it is replied to with a single SOA record of | the server's current version. [...] Thus, a client should first make an IXFR query using UDP. If the | query type is not recognized by the server, an AXFR (preceded by an | SOA query) should be tried, ensuring backward compatibility. [...]
Notes:
Rationale:
a) The behavior of the IXFR protocol described in the first paragraph
quoted above has been attributed falsely to AXFR; AXFR doesn't
behave like that (cf. the clarified AXFR specification in RFC 5936).
b) The SOA query may be performed over TCP as well, e.g., if there
already is an open TCP connection from the client to the server.
Historical Note:
The above issues have been identified by the submitter in 2008,
but no Errata have been filed so far. However, these already had
been observed in 1999 by Andreas Gustafsson, who, in the context of
the work on RFC 1995bis, recently has provided the DNSEXT WG access
to a privately archived DNSIND mailing list thread on RFC 1995,
in which these issues have been discussed in November 1999.
For the record, the technical issues in RFC 1995 that can be
addressed by Errata Notes are now being submitted this way.