CentOS - May 2014 - BIND Log file entries

This morning I see this in the syslog on our primary public DNS host.

    internal_send: 142.77.1.1#33950: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#35153: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#35644: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#49394: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#49816: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#49929: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#50281: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#50453: Connection timed out: 1 Time(s)
    internal_send: 142.77.1.1#50534: Connection timed out: 1 Time(s)
. . . (x100s)

 dig -x 142.77.1.1

; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.23.rc1.el6_5.1 <<>>
-x 142.77.1.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 31154
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 3, ADDITIONAL: 3

;; QUESTION SECTION:
;1.1.77.142.in-addr.arpa.	IN	PTR

;; ANSWER SECTION:
1.1.77.142.in-addr.arpa. 604800	IN	PTR	ns.uunet.ca.

;; AUTHORITY SECTION:
77.142.in-addr.arpa.	86400	IN	NS	ns.uunet.ca.
77.142.in-addr.arpa.	86400	IN	NS	AUTH01.NS.UU.NET.
77.142.in-addr.arpa.	86400	IN	NS	NS2.uunet.ca.

;; ADDITIONAL SECTION:
AUTH01.NS.UU.NET.	167	IN	A	198.6.1.81
ns.uunet.ca.		86400	IN	A	142.77.1.1
NS2.uunet.ca.		86400	IN	A	142.77.1.5

;; Query time: 114 msec
;; SERVER: 216.185.71.33#53(216.185.71.33)
;; WHEN: Thu May  1 09:59:50 2014
;; MSG SIZE  rcvd: 176



What is this and why is it happening?

-- 
***          E-Mail is NOT a SECURE channel          ***
James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
9 Brockley Drive              vox: +1 905 561 1241
Hamilton, Ontario             fax: +1 905 561 0757
Canada  L8E 3C3

On 2014-05-01 11:20, James B. Byrne wrote:
> This morning I see this in the syslog on our primary public DNS host.
> 
>     internal_send: 142.77.1.1#33950: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#35153: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#35644: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#49394: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#49816: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#49929: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#50281: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#50453: Connection timed out: 1 Time(s)
>     internal_send: 142.77.1.1#50534: Connection timed out: 1 Time(s)
> . . . (x100s)
> 
>  dig -x 142.77.1.1
> 
> ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.23.rc1.el6_5.1
<<>> -x 142.77.1.1
> ;; global options: +cmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 31154
> ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 3, ADDITIONAL: 3
> 
> ;; QUESTION SECTION:
> ;1.1.77.142.in-addr.arpa.	IN	PTR
> 
> ;; ANSWER SECTION:
> 1.1.77.142.in-addr.arpa. 604800	IN	PTR	ns.uunet.ca.
> 
> ;; AUTHORITY SECTION:
> 77.142.in-addr.arpa.	86400	IN	NS	ns.uunet.ca.
> 77.142.in-addr.arpa.	86400	IN	NS	AUTH01.NS.UU.NET.
> 77.142.in-addr.arpa.	86400	IN	NS	NS2.uunet.ca.
> 
> ;; ADDITIONAL SECTION:
> AUTH01.NS.UU.NET.	167	IN	A	198.6.1.81
> ns.uunet.ca.		86400	IN	A	142.77.1.1
> NS2.uunet.ca.		86400	IN	A	142.77.1.5
> 
> ;; Query time: 114 msec
> ;; SERVER: 216.185.71.33#53(216.185.71.33)
> ;; WHEN: Thu May  1 09:59:50 2014
> ;; MSG SIZE  rcvd: 176
> 
> 
> 
> What is this and why is it happening?
Some of my digging turns up the possibility that your system is trying 
to perform IPv6 DNS queries against an IPv4 DNS server.
-- 
Mike Burger
http://www.bubbanfriends.org

"It's always suicide-mission this, save-the-planet that. No one ever 
just stops by to say 'hi' anymore." --Colonel Jack O'Neill, SG1