BIND 9.11.4 dnstap not capturing updates

[greg.rabil at bt.com]

Thanks Tony, I see in the code now where it is not calling dns_dt_send() for the update request.

Regards,
Greg

> 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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