BIND 9.11.4 dnstap not capturing updates

[Tony Finch]

greg.rabil at bt.com <greg.rabil at bt.com> wrote:

> I use nsupdate to send a DDNS update to my zone, which is added
> successfully.  However, the dnstap.output does not record the DNS
> update.

I think (arguably) this is a limitation of the dnstap specification. It's
defined in a Protocol Buffers declaration file (see the link below) and it
only specifies message types for normal queries and responses. The types
correspond roughly to tap points in the code - it isn't as low-level as
you might expect, if you are imagining something that hooks into the
network IO layer.

If you want to record other kinds of messages (UPDATE, NOTIFY, etc.) it
would probably be best to extend the dnstap `Type` enum, and add
corresponding dns_dt_send() calls to BIND's code. But you should check
with Robert Edmonds first :-)

https://gitlab.isc.org/isc-projects/bind9/blob/master/lib/dns/dnstap.proto#L69

Tony.
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