长话短说.
挖c.cx
回报
; <<>> DiG 9.11.0-P2 <<>> c.cx ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY,status: NOERROR,id: 32806 ;; flags: qr rd ra; QUERY: 1,ANSWER: 1,AUTHORITY: 0,ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0,flags:; udp: 512 ;; QUESTION SECTION: ;c.cx. IN A ;; ANSWER SECTION: c.cx. 6903 IN A 0.0.0.0 ;; Query time: 90 msec ;; SERVER: 8.8.8.8#53(8.8.8.8) ;; WHEN: Mon Feb 06 22:33:08 +03 2017 ;; MSG SIZE rcvd: 49
一世.即地址0.0.0.0.
问题：
>它有什么特别的意义吗？
>它是否合法(dns记录可以包含哪些地址有限制)？
解决方法
这是合法的(见
RFC1035§3.4.1),但没用(因为它意味着“任何IP”).至于含义,请看一下
Zoneedit FAQ(这是错误的BTW,没有强制要求在域名本身上有A记录,恰恰相反,所有MTA都可以使用MX记录)：
32) Why can’t I delete the “A” record for the root name of my domain?
All domains must have an “A” record for the root of the domain. Omitting this “A” record may prevent some mail servers from delivering your email correctly. WebParking or WebForwarding the root of your domain is sufficient,because both of these create hidden “A” records pointing to our servers. If you’re really looking to delete this record,try changing the IP address to “0.0.0.0” instead,it’s functionally equivalent.
