Re: [DNSOP] Genart last call review of draft-ietf-dnsop-dns-tcp-requirements-12

Vladimír Čunát <vladimir.cunat+ietf@nic.cz> Mon, 13 September 2021 11:23 UTC

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Subject: Re: [DNSOP] Genart last call review of draft-ietf-dnsop-dns-tcp-requirements-12
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>> For the limit on total number of connections: "Absent any other 
>> information,
>> 150 is a reasonable value for this limit in most cases."
> [...]
> Maybe this could use a clarification that 150 is good advice only if 
> you _don't_ have any "TCP-only" clients, like e.g. DoT stubs?

I would not be so sure that DoT/DoH are the only cases.  What about busy 
authoritative servers?  You get 150 by default, and then some important 
RRset gets over the UDP limit (say, a DNSKEY rollover) and you get into 
problems due to overzealous connection limits.  IMHO 150 is extremely 
cheap for a (potentially) busy server.

--Vladimir | knot-resolver.cz