[dns-wg] NOTIFY

[Jim Reid <]

>>>>> "Peter" == Peter Koch pk@localhost writes:

    >> As it happens we use probing not NOTIFY since it gives a
    >> greater level of control over the number of secondaries being
    >> updated at once (and the

    Peter> NOTIFY already specifies precautions against a 'rush',
    Peter> although implementations may differ and depending on the
    Peter> size of the zone 'at once' may have different meanings.

Yes. But BIND's implementation of this feature is meant for the case
when there are lots of zones that get changed and reloaded. [And there
are no control hooks for setting the delay interval IIRC.] The server
staggers the sending of NOTIFYs to reduce the potential for an axfr
storm. The feature doesn't really help when there's a huge zone. Like
co.uk...

    >> bandwidth) and the order in which they are updated.  This does
    >> rely on strict calculations of the timings of changes and
    >> probes but that is fairly easy to do.

    Peter> How about sending the NOTIFY messages out of band instead
    Peter> of relying upon retry (and not refresh?)? There's a little
    Peter> 'DoS' potential, though.

How about rndc refresh or rndc retransfer in 9.3? It's not really an
out of band NOTIFY, though the effect is the same.


Note the new Subject since this thread isn't talking abouut an
analysis of NSD any more.