Re: [knot-dns-users] outgoing NOTIFYs over TCP

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 :-/