[Pdns-users] Intermittent SERVFAIL Response

[Scott Hollenbeck]

I'm running PowerDNS Recursor 3.7.3 on a pair of Ubuntu 14.04.3 LTS servers.
I'm getting intermittent SERVFAIL responses on both servers to queries for a
particular name. Could someone please help me understand what might be
causing these failures? Here are examples of the SERVFAIL responses I'm
seeing on one of the servers:

$ dig @localhost www.concoursmustang.com any

; <<>> DiG 9.9.5-3ubuntu0.4-Ubuntu <<>> @localhost www.concoursmustang.com
any
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 23134
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.concoursmustang.com.       IN      ANY

;; Query time: 3004 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Tue Aug 18 09:31:23 EDT 2015
;; MSG SIZE  rcvd: 41

$ dig @localhost www.concoursmustang.com a

; <<>> DiG 9.9.5-3ubuntu0.4-Ubuntu <<>> @localhost www.concoursmustang.com a
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 29329
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.concoursmustang.com.       IN      A

;; Query time: 3003 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Tue Aug 18 09:36:28 EDT 2015
;; MSG SIZE  rcvd: 41

A successful result for a different domain:

$ dig @localhost powerdns.com a

; <<>> DiG 9.9.5-3ubuntu0.4-Ubuntu <<>> @localhost powerdns.com a
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 53794
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;powerdns.com.                  IN      A

;; ANSWER SECTION:
powerdns.com.           40190   IN      A       82.94.213.34

;; Query time: 1 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Tue Aug 18 09:41:27 EDT 2015
;; MSG SIZE  rcvd: 46

Successful queries on the second server:

$ dig @localhost www.concoursmustang.com a

; <<>> DiG 9.9.5-3ubuntu0.4-Ubuntu <<>> @localhost www.concoursmustang.com a
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 40855
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.concoursmustang.com.       IN      A

;; ANSWER SECTION:
www.concoursmustang.com. 14400  IN      CNAME   concoursmustang.com.
concoursmustang.com.    14400   IN      A       70.40.195.107

;; Query time: 64 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Tue Aug 18 09:35:55 EDT 2015
;; MSG SIZE  rcvd: 71

$ dig @localhost www.concoursmustang.com any

; <<>> DiG 9.9.5-3ubuntu0.4-Ubuntu <<>> @localhost www.concoursmustang.com
any
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6474
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.concoursmustang.com.       IN      ANY

;; ANSWER SECTION:
www.concoursmustang.com. 14385  IN      CNAME   concoursmustang.com.
concoursmustang.com.    40278   IN      NS      ns2.hostmonster.com.
concoursmustang.com.    14385   IN      A       70.40.195.107
concoursmustang.com.    40278   IN      NS      ns1.hostmonster.com.

;; Query time: 0 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Tue Aug 18 09:36:10 EDT 2015
;; MSG SIZE  rcvd: 119

These servers are configured similarly. Both are configured to accept
queries only from machines on my local network.

Thanks,
Scott