DNS/毒盛/CNAME/twimgについて、ここに記述してください。

$ dig +norec -t a pbs\.twimg\.com @ns4\.p34\.dynect\.net.
{{{
; <<>> DiG 9.9.5-3ubuntu0.9-Ubuntu <<>> +norec -t a pbs.twimg.com @ns4.p34.dynect.net.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 47180
;; flags: qr aa; QUERY: 1, ANSWER: 3, AUTHORITY: 4, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;pbs.twimg.com.			IN	A

;; ANSWER SECTION:
pbs.twimg.com.		300	IN	CNAME	wildcard.twimg.com.
wildcard.twimg.com.	1800	IN	A	104.244.43.39
wildcard.twimg.com.	1800	IN	A	104.244.43.103

;; AUTHORITY SECTION:
twimg.com.		1800	IN	NS	ns2.p34.dynect.net.
twimg.com.		1800	IN	NS	ns1.p34.dynect.net.
twimg.com.		1800	IN	NS	ns4.p34.dynect.net.
twimg.com.		1800	IN	NS	ns3.p34.dynect.net.

;; Query time: 8 msec
;; SERVER: 204.13.251.34#53(204.13.251.34)
;; WHEN: Tue Nov 01 09:30:31 JST 2016
;; MSG SIZE  rcvd: 183
}}}

$ dig +norec -t a pbs\.twimg\.com @ns4\.p34\.dynect\.net.
{{{
; <<>> DiG 9.9.5-3ubuntu0.9-Ubuntu <<>> +norec -t a pbs.twimg.com @ns4.p34.dynect.net.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 11812
;; flags: qr aa; QUERY: 1, ANSWER: 3, AUTHORITY: 4, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;pbs.twimg.com.			IN	A

;; ANSWER SECTION:
pbs.twimg.com.		300	IN	CNAME	wildcard.twimg.com.
wildcard.twimg.com.	1800	IN	A	104.244.43.71
wildcard.twimg.com.	1800	IN	A	104.244.43.231

;; AUTHORITY SECTION:
twimg.com.		1800	IN	NS	ns3.p34.dynect.net.
twimg.com.		1800	IN	NS	ns2.p34.dynect.net.
twimg.com.		1800	IN	NS	ns1.p34.dynect.net.
twimg.com.		1800	IN	NS	ns4.p34.dynect.net.

;; Query time: 7 msec
;; SERVER: 204.13.251.34#53(204.13.251.34)
;; WHEN: Tue Nov 01 09:31:00 JST 2016
;; MSG SIZE  rcvd: 183

tmaeno@tm:~$ dig +norec -t a pbs\.twimg\.com @ns4\.p34\.dynect\.net.

; <<>> DiG 9.9.5-3ubuntu0.9-Ubuntu <<>> +norec -t a pbs.twimg.com @ns4.p34.dynect.net.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 58487
;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;pbs.twimg.com.			IN	A

;; ANSWER SECTION:
pbs.twimg.com.		300	IN	CNAME	cs196.wac.edgecastcdn.net.

;; Query time: 121 msec
;; SERVER: 204.13.251.34#53(204.13.251.34)
;; WHEN: Tue Nov 01 09:31:17 JST 2016
;; MSG SIZE  rcvd: 81
}}}