Hi Daniel,
I don't run Knot DNS as a master, so I don't see this issue. Even if I
ran Knot DNS as a master, I'm not terribly bothered with NOTIFY over TCP.
Having said that, I don't think it's very fair to say that UDP is
unreliable, and there are various reasons for it:
1. NOTIFY is a hint, and if it gets lost, it's not the biggest disaster
in the world.
2. NOTIFY is just like any other query, so Knot could send the NOTIFY
over UDP and wait for the response. If the response doesn't arrive, it
could retry the NOTIFY. At least BIND and NSD both do this. They allow
for the fact that one NOTIFY might get lost sometimes.
However, if you can't easily modify Knot to use UDP instead of TCP for
NOTIFY, it doesn't bother me personally, because a NOTIFY receiver
should also be able to accept TCP (TCP is required by DNS). But I can
see Klaus's viewpoint. However, I'll leave him to tell us his opinion on
this matter.
Regards,
Anand
On 08/06/2018 14:11, Daniel Salzman wrote:
Hi Klaus,
Knot DNS always sends NOTIFY over TCP. It's intentional, because UDP is unreliable.
Unfortunately, it's not possible to easily switch to UDP :-/