Here's a chart summarizing the situation:
Timing of |Useful in|RFC 1034 |BIND 8 |BIND 9 |tinydns
data change |practice |compliant|support|support|support
------------------+---------+---------+-------+-------+-------
Synchronized |Yes |Yes |No |No |Yes
Semi-synchronized |Yes |No |Yes |Yes |Yes
Unsynchronized |No |No |No |Yes |No
The BIND company observes that
* synchronized changes are hard to do with BIND, even though they're
required by RFC 1034; and
* unsynchronized changes can fail miserably with BIND 8 et al., which
account for the majority of DNS servers.
The obvious solution is semi-synchronized changes, which work with the
entire installed base. I wouldn't object to modifying RFC 1034 to allow
semi-synchronized changes.
(To repeat the relevant definitions: A synchronized change happens at
the same time in all the parent servers and all the child servers. A
semi-synchronized change happens in the parent zone---specifically, the
parent serial is changed---after it happens in all the child servers.)
I certainly _do_ object to allowing unsynchronized changes. They don't
work correctly with the installed base, and they have no advantages over
semi-synchronized changes. It's insane to demand massive redeployment of
DNS servers for the sake of a useless protocol modification.
Mark(_dot_)Andrews(_at_)isc(_dot_)org writes:
you need to write up a draft
_I_ don't need to write anything. I am not the one trying to change the
requirements in RFC 1034. My software follows the spec.
_Your_ company is trying to impose requirements that aren't in RFC 1034.
You are claiming that most DNS server installations on the Internet have
to be changed. You are demanding that we tolerate configurations that
violate RFC 1034.
Even worse, instead of honestly proposing this protocol change, you are
trying to sneak it past us as part of an ``AXFR clarification''; and
someone who has been paid for BIND work is abusing his position as WG
chair by fraudulently claiming ``consensus.'' This is a sham.
---D. J. Bernstein, Associate Professor, Department of Mathematics,
Statistics, and Computer Science, University of Illinois at Chicago