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domain name system - Intermittent recursive/iterative DNS query failure

I have a problem issuing queries to a DNS and I'm not sure where to look for the underlying cause.



I have a record "www.alumninews.uottawa.ca" which is a CNAME record which points to an A record for "uottawa.mailoutinteractive.com" which I host. When I query my ISP's DNS servers, I get different responses:




The first does not recurse



$ dig +recurse www.alumninews.uottawa.ca @64.59.184.13

; <<>> DiG 9.8.1-P1 <<>> +recurse www.alumninews.uottawa.ca @64.59.184.13
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 13260
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0


;; QUESTION SECTION:
;www.alumninews.uottawa.ca. IN  A

;; ANSWER SECTION:
www.alumninews.uottawa.ca. 3600 IN  CNAME   uottawa.mailoutinteractive.com.

;; Query time: 139 msec
;; SERVER: 64.59.184.13#53(64.59.184.13)
;; WHEN: Wed Apr  3 11:33:55 2013
;; MSG SIZE  rcvd: 87



Note that the CNAME does not get resolved (more on that below).



The second resolves the CNAME correctly (note the TTL is now 3532, not the default 3600 above): 



$ dig +recurse www.alumninews.uottawa.ca @64.59.184.13

; <<>> DiG 9.8.1-P1 <<>> +recurse www.alumninews.uottawa.ca @64.59.184.13
;; global options: +cmd

;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 16716
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.alumninews.uottawa.ca. IN  A

;; ANSWER SECTION:
www.alumninews.uottawa.ca. 3532 IN  CNAME   uottawa.mailoutinteractive.com.
uottawa.mailoutinteractive.com. 300 IN  A   209.15.195.166


;; Query time: 30 msec
;; SERVER: 64.59.184.13#53(64.59.184.13)
;; WHEN: Wed Apr  3 11:35:03 2013
;; MSG SIZE  rcvd: 103


Further, when I capture the network traffic with wireshark, I'm seeing that the error when looking up uottawa.mailoutinteractive.com is "Reply code: No such name (3)" on the failed recursion:



Domain Name System (response)

[Request In: 3993]
[Time: 0.057954000 seconds]
Transaction ID: 0xf07c
Flags: 0x8183 Standard query response, No such name
    1... .... .... .... = Response: Message is a response
    .000 0... .... .... = Opcode: Standard query (0)
    .... .0.. .... .... = Authoritative: Server is not an authority for domain
    .... ..0. .... .... = Truncated: Message is not truncated
    .... ...1 .... .... = Recursion desired: Do query recursively
    .... .... 1... .... = Recursion available: Server can do recursive queries

    .... .... .0.. .... = Z: reserved (0)
    .... .... ..0. .... = Answer authenticated: Answer/authority portion was not authenticated by the server
    .... .... ...0 .... = Non-authenticated data: Unacceptable
    .... .... .... 0011 = Reply code: No such name (3)
Questions: 1
Answer RRs: 1
Authority RRs: 0
Additional RRs: 0
Queries
    www.alumninews.uottawa.ca: type A, class IN

        Name: www.alumninews.uottawa.ca
        Type: A (Host address)
        Class: IN (0x0001)
Answers
    www.alumninews.uottawa.ca: type CNAME, class IN, cname uottawa.mailoutinteractive.com
        Name: www.alumninews.uottawa.ca
        Type: CNAME (Canonical name for an alias)
        Class: IN (0x0001)
        Time to live: 1 hour
        Data length: 32

        Primaryname: uottawa.mailoutinteractive.com


A successful lookup looks like this in Wireshark (this is a different domain with the same problem):



Domain Name System (response)
[Request In: 70]
[Time: 0.051422000 seconds]
Transaction ID: 0x417d
Flags: 0x8180 Standard query response, No error

    1... .... .... .... = Response: Message is a response
    .000 0... .... .... = Opcode: Standard query (0)
    .... .0.. .... .... = Authoritative: Server is not an authority for domain
    .... ..0. .... .... = Truncated: Message is not truncated
    .... ...1 .... .... = Recursion desired: Do query recursively
    .... .... 1... .... = Recursion available: Server can do recursive queries
    .... .... .0.. .... = Z: reserved (0)
    .... .... ..0. .... = Answer authenticated: Answer/authority portion was not authenticated by the server
    .... .... ...0 .... = Non-authenticated data: Unacceptable
    .... .... .... 0000 = Reply code: No error (0)

Questions: 1
Answer RRs: 2
Authority RRs: 0
Additional RRs: 0
Queries
    www.bulletinsanciens.uottawa.ca: type A, class IN
        Name: www.bulletinsanciens.uottawa.ca
        Type: A (Host address)
        Class: IN (0x0001)
Answers

    www.bulletinsanciens.uottawa.ca: type CNAME, class IN, cname uottawa.mailoutinteractive.com
        Name: www.bulletinsanciens.uottawa.ca
        Type: CNAME (Canonical name for an alias)
        Class: IN (0x0001)
        Time to live: 41 minutes, 26 seconds
        Data length: 32
        Primaryname: uottawa.mailoutinteractive.com
    uottawa.mailoutinteractive.com: type A, class IN, addr 209.15.195.166
        Name: uottawa.mailoutinteractive.com
        Type: A (Host address)

        Class: IN (0x0001)
        Time to live: 5 minutes
        Data length: 4
        Addr: 209.15.195.166 (209.15.195.166)


Uottawa's DNS servers are configured not to return recursive query information, so my understanding is that my ISP will do a second query to resolve the CNAME. But I don't know why it is failing once and then succeeeding a second time. It seems to me to be a problem between our ISP (Shaw) and Route53, where my DNS is hosted.



I also notice that it often continues to fail---I can continue to execute the failing dig command for quite a while before it succeeds again.




I've gotten this far but don't know how to debug this any further. Any idea where this is failing?

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