答案1
问题中指出的查找是为了NS
记录。
NS
记录用于将区域委托给权威名称服务器,并存在于每个区域的起点。
在您的示例中,codeproject.com
是区域的起点(即,它与区域分开com
)但www.codeproject.com
只是区域内的名称codeproject.com
,因此没有NS
自己的记录。
答案2
您的域名不带 www,有ns
:
# dig codeproject.com ns
; <<>> DiG 9.9.5-12.1-Debian <<>> codeproject.com ns
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19623
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;codeproject.com. IN NS
;; ANSWER SECTION:
codeproject.com. 229 IN NS ns1.easydns.com.
codeproject.com. 229 IN NS service1.codeproject.com.
codeproject.com. 229 IN NS ns2.easydns.com.
codeproject.com. 229 IN NS service2.codeproject.com.
;; Query time: 43 msec
;; SERVER: 85.15.1.15#53(85.15.1.15)
;; WHEN: Mon May 09 02:11:48 IRDT 2016
;; MSG SIZE rcvd: 134
但是您的带有 www 的域名没有ns
:
# dig www.codeproject.com ns
; <<>> DiG 9.9.5-12.1-Debian <<>> www.codeproject.com ns
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29227
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;www.codeproject.com. IN NS
;; AUTHORITY SECTION:
codeproject.com. 299 IN SOA service1.codeproject.com. david.cunningham.codeproject.com. 2016020214 7200 1200 432000 300
;; Query time: 173 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Mon May 09 02:13:14 IRDT 2016
;; MSG SIZE rcvd: 110