然后我在test.example.com上创建一条A记录到1.1.1.1.
然后我在test.example.com上创建一条NS记录到ns1.anotherdnshost.com.
在另一个DNS主机上,我将根(test.example.com)的A记录添加到2.2.2.2.
当客户端查询test.example.com时,将返回哪条A记录?哪个更具“优势”A记录?这样的设置有效吗?
解决方法
现在列出区域中的其他NS记录是正确的,但另一个NS应该是具有相同区域的名称服务器.但是,您可以将子域指向备用名称服务器.
因此,您的注册商的example.com指向ns1.example.com和ns2.example.com,其中1.2.3.4和2.3.4.5来自注册商名称服务器(胶水).
然后,您将有一个SOA选择ns1或ns2作为主要区域的区域,然后您将有两个NS记录指向ns1.example.com和ns2.example.com,其中包含该域的A记录(以及mx,txt),cname等).
NS1和NS2.example.com都应该具有相同的区域,并且它们应该自动复制到彼此.
现在它是有效的,采取test.example.com并指向ns1.somethingelse.com和ns2.somethingelse.com但在ns1和ns2.example.com的名称服务器上的test.example.com没有记录,除了ns1和如果有粘连,ns2.example.com应自动发送ns1和ns2.somethingelse.com的IP. (如果TLD不同,即.com和.org不会)
我希望一切都有意义,如果有任何混淆,我可以澄清更多.
这是对发生的事情的测试:
在shadowrpg.net的名称服务器上:
$ttl 38400 @ IN SOA shell2.reganw.com. root.shell2.reganw.com. ( 1298345653 10800 3600 604800 38400 ) @ IN NS shell2.reganw.com. test.shadowrpg.net. IN A 127.0.0.1 test.shadowrpg.net. IN NS saber.reganw.com.
在test.shadowrpg.net的名称服务器(saber):
$ttl 38400 @ IN SOA saber.reganw.com. root.shell2.reganw.com. ( 1298345653 10800 3600 604800 38400 ) @ IN NS saber.reganw.com. test.shadowrpg.net. IN A 127.0.0.2 test.shadowrpg.net. IN NS saber.reganw.com.
第一个结果是未配置军刀,以显示推荐.
[regan@gamma ~]$dig +trace test.shadowrpg.net ; <<>> DiG 9.7.3-P1-RedHat-9.7.3-2.P1.fc13 <<>> +trace test.shadowrpg.net ;; global options: +cmd . 518400 IN NS G.ROOT-SERVERS.NET. . 518400 IN NS C.ROOT-SERVERS.NET. (snip) ;; Received 512 bytes from 127.0.0.1#53(127.0.0.1) in 2 ms net. 172800 IN NS a.gtld-servers.net. net. 172800 IN NS m.gtld-servers.net. (snip) ;; Received 493 bytes from 199.7.83.42#53(199.7.83.42) in 55 ms shadowrpg.net. 172800 IN NS ns1.reganw.com. shadowrpg.net. 172800 IN NS ns2.reganw.com. shadowrpg.net. 172800 IN NS ns3.reganw.com. ;; Received 232 bytes from 192.35.51.30#53(192.35.51.30) in 54 ms test.shadowrpg.net. 38400 IN NS saber.reganw.com. ;; Received 110 bytes from 209.161.6.3#53(209.161.6.3) in 2123 ms test.shadowrpg.net. 38400 IN NS saber.reganw.com. ;; BAD (HORIZONTAL) REFERRAL ;; Received 110 bytes from 173.45.238.245#53(173.45.238.245) in 81 ms test.shadowrpg.net. 38400 IN NS saber.reganw.com. ;; BAD (HORIZONTAL) REFERRAL ;; Received 110 bytes from 173.45.238.245#53(173.45.238.245) in 82 ms test.shadowrpg.net. 38400 IN NS saber.reganw.com. ;; BAD (HORIZONTAL) REFERRAL ;; Received 110 bytes from 173.45.238.245#53(173.45.238.245) in 112 ms
并配有军刀:
^C[regan@gamma ~]$dig +trace test.shadowrpg.net ; <<>> DiG 9.7.3-P1-RedHat-9.7.3-2.P1.fc13 <<>> +trace test.shadowrpg.net ;; global options: +cmd . 518400 IN NS L.ROOT-SERVERS.NET. . 518400 IN NS J.ROOT-SERVERS.NET. (snip) ;; Received 512 bytes from 127.0.0.1#53(127.0.0.1) in 2 ms net. 172800 IN NS m.gtld-servers.net. net. 172800 IN NS a.gtld-servers.net. (snip) ;; Received 493 bytes from 198.41.0.4#53(198.41.0.4) in 129 ms shadowrpg.net. 172800 IN NS ns1.reganw.com. shadowrpg.net. 172800 IN NS ns2.reganw.com. shadowrpg.net. 172800 IN NS ns3.reganw.com. ;; Received 232 bytes from 192.12.94.30#53(192.12.94.30) in 165 ms test.shadowrpg.net. 38400 IN NS saber.reganw.com. ;; Received 110 bytes from 209.161.6.3#53(209.161.6.3) in 38 ms test.shadowrpg.net. 38400 IN A 127.0.0.2 test.shadowrpg.net. 38400 IN NS saber.reganw.com. ;; Received 126 bytes from 173.45.238.245#53(173.45.238.245) in 80 ms [regan@gamma ~]$
因此,一旦添加了NS记录,它就会引用它,并且它会忽略对自身的任何查询.现在,如果为名称服务器添加A记录,它将以NS记录作为粘合剂传递(因此解析器不必查找新名称服务器的IP).