[dns-operations] domain in .no, nameserver in .com - where is the glue?

[Andreas Pettersson]

Q1:
How "bad" is it to have a domain's name servers under another TLD?
For example, apple.no has all NS's under .com.

Q2:
When doing a dig trace for www.apple.no, I don't see any lookups for 
.com-addresses. How does the resolver find the A record for the name 
servers?

# dig +trace a www.apple.no

; <<>> DiG 9.3.3 <<>> +trace a www.apple.no
;; global options:  printcmd
.                       311456  IN      NS      I.ROOT-SERVERS.NET.
.                       311456  IN      NS      G.ROOT-SERVERS.NET.
.                       311456  IN      NS      A.ROOT-SERVERS.NET.
.                       311456  IN      NS      L.ROOT-SERVERS.NET.
.                       311456  IN      NS      F.ROOT-SERVERS.NET.
.                       311456  IN      NS      D.ROOT-SERVERS.NET.
.                       311456  IN      NS      H.ROOT-SERVERS.NET.
.                       311456  IN      NS      J.ROOT-SERVERS.NET.
.                       311456  IN      NS      B.ROOT-SERVERS.NET.
.                       311456  IN      NS      K.ROOT-SERVERS.NET.
.                       311456  IN      NS      C.ROOT-SERVERS.NET.
.                       311456  IN      NS      E.ROOT-SERVERS.NET.
.                       311456  IN      NS      M.ROOT-SERVERS.NET.
;; Received 436 bytes from 195.67.199.24#53(195.67.199.24) in 12 ms

no.                     172800  IN      NS      Y.NIC.no.
no.                     172800  IN      NS      Z.NIC.no.
no.                     172800  IN      NS      NOT.NORID.no.
no.                     172800  IN      NS      NJET.NORID.no.
no.                     172800  IN      NS      I.NIC.no.
no.                     172800  IN      NS      X.NIC.no.
;; Received 237 bytes from 192.36.148.17#53(I.ROOT-SERVERS.NET) in 19 ms

apple.no.               86400   IN      NS      nserver.euro.apple.com.
apple.no.               86400   IN      NS      nserver.apple.com.
apple.no.               86400   IN      NS      nserver2.apple.com.
;; Received 111 bytes from 193.71.199.51#53(Y.NIC.no) in 29 ms

www.apple.no.           86400   IN      CNAME   euro-red.apple.com.
euro-red.apple.com.     86400   IN      A       17.254.3.122
apple.com.              432000  IN      NS      nserver.euro.apple.com.
apple.com.              432000  IN      NS      nserver.apple.com.
apple.com.              432000  IN      NS      nserver2.apple.com.
apple.com.              432000  IN      NS      nserver3.apple.com.
apple.com.              432000  IN      NS      nserver4.apple.com.
apple.com.              432000  IN      NS      nserver.asia.apple.com.
;; Received 319 bytes from 17.72.133.64#53(nserver.euro.apple.com) in 62 ms


(The first server queried 195.67.199.24 is my ISP's DNS)

-- 
Andreas