Observation: BIND 9.18 qname-minimization strict vs dig +trace

[Havard Eidnes]

> The facts are:
>
>   * 191.131.in-addr.arpa is served from awsdns

Correct.  And it's delegated to from the 131.in-addr.arpa zone,
maintained by ARIN.

>   * It delegates 85.191.131.in-addr.arpa with fs838.click-network.com
>     and ns102.click-network.com above the zone cut.

Correct.

>   * Below the zone cut the nameserver claims to be authoritative for its
>     parent's zone (191.131.in-addr.arpa) instead of
>     85.191.131.in-addr.arpa. (In other words it's lame.)

Well, yes.  When queried for the NS set for 85.191.131.in-addr.arpa it
returns "NOERROR" with the 191.131.in-addr.arpa SOA record in the
authority section.  This is what is called an "upward referral", and
indicates that the delegation structure and/or child name server setup
is inconsistent with the delegation structure.  Were I less charitable
I would say "messed up".  Basically what you say above -- it doesn't
serve the delegated zone so is "lame".

>   * (Below the zone cut it also erroneously advertises one of its
>     nameservers as simply ns102. instead of ns102.click-network.com)

Yep.

>   * There is no server which actually advertises itself as authoritative
>     for 85.191.131.in-addr.arpa

Yep.  Both of the resolveable NSes ns102.click-network.com and
fs838.click-network.com claim authority over 191.131.in-addr.arpa,
which they don't have according to the parent zone DNS delegations.

Regards,

- Håvard