也许该特定主机的DNS服务器已关闭;请检查域的whois
记录以发现哪些DNS服务器具有权威性,然后依次使用host
检查它们中的每一个,以确定它们全部解决。
例如,whois stackoverflow.com
:
Name Servers:
ns1.serverfault.com
ns2.serverfault.com
ns3.serverfault.com
然后:
$ host www.stackoverflow.com ns1.serverfault.com
Using domain server:
Name: ns1.serverfault.com
Address: 64.34.119.33#53
Aliases:
www.stackoverflow.com is an alias for stackoverflow.com.
stackoverflow.com has address 64.34.119.12
stackoverflow.com mail is handled by 10 STACKOVERFLOW.COM.S9A1.PSMTP.com.
stackoverflow.com mail is handled by 20 STACKOVERFLOW.COM.S9A2.PSMTP.com.
stackoverflow.com mail is handled by 30 STACKOVERFLOW.COM.S9B1.PSMTP.com.
stackoverflow.com mail is handled by 40 STACKOVERFLOW.COM.S9B2.PSMTP.com.
$ host www.stackoverflow.com ns2.serverfault.com
Using domain server:
Name: ns2.serverfault.com
Address: 64.34.119.34#53
Aliases:
www.stackoverflow.com is an alias for stackoverflow.com.
stackoverflow.com has address 64.34.119.12
stackoverflow.com mail is handled by 30 STACKOVERFLOW.COM.S9B1.PSMTP.com.
stackoverflow.com mail is handled by 40 STACKOVERFLOW.COM.S9B2.PSMTP.com.
stackoverflow.com mail is handled by 10 STACKOVERFLOW.COM.S9A1.PSMTP.com.
stackoverflow.com mail is handled by 20 STACKOVERFLOW.COM.S9A2.PSMTP.com.
$ host www.stackoverflow.com ns3.serverfault.com
Using domain server:
Name: ns3.serverfault.com
Address: 69.59.196.217#53
Aliases:
www.stackoverflow.com is an alias for stackoverflow.com.
stackoverflow.com has address 64.34.119.12
stackoverflow.com mail is handled by 30 STACKOVERFLOW.COM.S9B1.PSMTP.com.
stackoverflow.com mail is handled by 40 STACKOVERFLOW.COM.S9B2.PSMTP.com.
stackoverflow.com mail is handled by 10 STACKOVERFLOW.COM.S9A1.PSMTP.com.
stackoverflow.com mail is handled by 20 STACKOVERFLOW.COM.S9A2.PSMTP.com.
$
三台服务器响应请求www.stackoverflow.com
,所以这三个服务器的功能。
你可以ping每台服务器吗? –