Question about swupdl.adobe.com

[Tony Finch]

Giles Coochey <giles at coochey.net> wrote:

> It looks like adobe are entertaining use of a CNAME chain (a CNAME to a CNAME
> which points to a CNAME which points to a CNAME which eventually points to an
> A record).

No, CNAME chains are OK. The problem is that the wip4.adobe.com name
servers incorrectly respond with NXDOMAIN (instead of noerror/nodata) when
you ask for RRtypes other than A and AAAA.

; <<>> DiG 9.11.0pre-alpha <<>> mx swupdl.adobe.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 36234
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;swupdl.adobe.com.              IN      MX

;; ANSWER SECTION:
swupdl.adobe.com.       2976    IN      CNAME   swupdl.wip4.adobe.com.

;; AUTHORITY SECTION:
wip4.adobe.com.         30      IN      SOA     sj1gtm001.adobe.com. hostmaster.sj1gtm001.adobe.com. 1287 10800 3600 604800 60

;; Query time: 169 msec
;; SERVER: ::1#53(::1)
;; WHEN: Thu Oct 09 14:41:01 BST 2014
;; MSG SIZE  rcvd: 128

Tony.
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