[dns-operations] Lame delegation in .CD with a NS . and non answering NS

[Mark Andrews]

It really depends on what is cached.  NS records that point at CNAMEs do
not work reliably.

ns1.shivanet.net.	14367	IN	CNAME	ns1.bh-61.webhostbox.net.
ns1.bh-61.webhostbox.net. 269	IN	A	204.11.59.195

And you have nameservers set up like this:

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 20197
;; flags: qr aa ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags: do; udp: 4096
;; QUESTION SECTION:
;ns1.shivanet.net.		IN	A

;; ANSWER SECTION:
ns1.shivanet.net.	14400	IN	CNAME	ns1.bh-61.webhostbox.net.

;; AUTHORITY SECTION:
.			3600	IN	NS	ns2.
.			3600	IN	NS	ns1.

;; Query time: 294 msec
;; SERVER: 204.11.59.195#53(204.11.59.195)
;; WHEN: Tue Jan 09 10:34:33 AEDT 2018
;; MSG SIZE  rcvd: 112


-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742              INTERNET: marka at isc.org