测试环境:连接了 ISATAP 的阿里云和 DO-SGP
dig @2001:4860:4860::8888 www.aliyun.com
; <<>> DiG 9.10.5 <<>> @2001:4860:4860::8888 www.aliyun.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 63895
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;www.aliyun.com. IN A
;; Query time: 4147 msec
;; SERVER: 2001:4860:4860::8888#53(2001:4860:4860::8888)
;; WHEN: Sat Sep 30 06:21:19 UTC 2017
;; MSG SIZE rcvd: 43