DDNS, Notify and IXFR

[Bob Halley]

halley>  I think we're going to need to rate-limit NOTIFY generation in the
halley>  future.

ogud>  Yes we need that, or we need to delete IXFR as a protocol and replace 
ogud>  with something MUCH better.

The issues Kevin raised are not the fault of the IXFR protocol.

They are due to interactions between BIND's implementations of
deferred serial number update, NOTIFY, and IXFR.  Changing the
implementation, for example by rate-limiting NOTIFY generation, should
solve the problem.

/Bob