Hi Duane, Thank you for your answer and for addressing my concerns. I am fine with the proposed resolutions.
Regards, Dan On Tue, Sep 7, 2021 at 7:46 PM Wessels, Duane <dwess...@verisign.com> wrote: > Dan, thanks for the review. Responses are inline. > > > > > On Sep 1, 2021, at 3:12 AM, Dan Romascanu via Datatracker < > nore...@ietf.org> wrote: > > > > > > Minor issues: > > > > 1. In Section 4.1: > > > >> DNS clients MAY also enable TFO when possible. > > > > Maybe I do not fully understand the intent here, but 'MAY ... when > possible' > > sounds like a SHOULD to me. > > > Originally this was "SHOULD ... when possible" (meaning when > implemented/supported) but after conversations with tcpm this was changed > to MAY. To avoid confusion with "when possible" I suggest we just drop > it so it will just say "DNS clients MAY also enable TFO." > > > > > > > 2.In Section 4.2 > > > >> DNS server software SHOULD provide a configurable limit on the total > > number of established TCP connections. If the limit is reached, the > > application is expected to either close existing (idle) connections > > or refuse new connections. Operators SHOULD ensure the limit is > > configured appropriately for their particular situation. > > > > DNS server software MAY provide a configurable limit on the number of > > established connections per source IP address or subnet. This can be > > used to ensure that a single or small set of users cannot consume all > > TCP resources and deny service to other users. Operators SHOULD > > ensure this limit is configured appropriately, based on their number > > of diversity of users. > > > > The lack of recommendations about how these limits should be set would > leave > > less experienced operators in the dark. There is not even a sentence > like 'This > > document does not offer advice on particular values for such a limit' as > for > > other parameters in the same section. From an operators point of view I > would > > prefer a recommendation or one or more examples of how these limits can > be set > > in real life cases. > > Other reviewers called this out as well so I have added some recommended > values. > > For the limit on total number of connections: "Absent any other > information, > 150 is a reasonable value for this limit in most cases." > > For the limit on connections per source address: "Absent any other > information, 25 is a reasonable value for this limit in most cases." > > For the timeout on idle connections: "Absent any other information, 10 > seconds is a reasonable value for this timeout in most cases." > > > > > > Nits/editorial comments: > > > > 1. Sections in the document that are obviously for informational > pursposes > > should be clearly marked so (like 'This section is included for > informational > > purposes only'). For example Section 2. > > Done. > > > > > > 2. In Section 3: > > > > Regarding the choice of limiting the resources a server devotes to > > queries, Section 6.1.3.2 in [RFC1123] also says: > > > > "A name server MAY limit the resources it devotes to TCP queries, > > but it SHOULD NOT refuse to service a TCP query just because it > > would have succeeded with UDP." > > > > This requirement is hereby updated: A name server MAY limit the > > resources it devotes to queries, but it MUST NOT refuse to service a > > query just because it would have succeeded with another transport > > protocol. > > > > Similar alignment of the old and new text is desirable. Even using the > OLD / > > NEW format. > > Good point. Section 3 now looks like this: > > Section 6.1.3.2 in [RFC1123] is updated: All DNS resolvers and > servers MUST support and service both UDP and TCP queries. > > o Authoritative servers MUST support and service all TCP queries so > that they do not limit the size of responses to what fits in a > single UDP packet. > > o Recursive servers (or forwarders) MUST support and service all TCP > queries so that they do not prevent large responses from a TCP- > capable server from reaching its TCP-capable clients. > > Furthermore, the requirement in Section 6.1.3.2 of [RFC1123] around > limiting the resources a server devotes to queries is hereby updated: > > OLD: > > A name server MAY limit the resources it devotes to TCP queries, > but it SHOULD NOT refuse to service a TCP query just because it > would have succeeded with UDP. > > NEW: > > A name server MAY limit the resources it devotes to queries, but > it MUST NOT refuse to service a query just because it would have > succeeded with another transport protocol. > > > > FYI we are tracking this in github at > https://github.com/jtkristoff/draft-ietf-dnsop-dns-tcp-requirements/pull/4/files > if that is helpful. > > DW > >
_______________________________________________ Gen-art mailing list Gen-art@ietf.org https://www.ietf.org/mailman/listinfo/gen-art
