Dns ping回复中的主机名来自哪里?
当我从同一子网中的计算机ping IP地址时,以下是回复:Dns ping回复中的主机名来自哪里?,dns,ping,Dns,Ping,当我从同一子网中的计算机ping IP地址时,以下是回复: root@dia11:~# ping B.test.com PING B.test.com (10.1.128.76) 56(84) bytes of data. 64 bytes from A.test.com (10.1.128.76): icmp_seq=1 ttl=62 time=4.85 ms 64 bytes from A.test.com (10.1.128.76): icmp_seq=2 ttl=62 time=5.44
root@dia11:~# ping B.test.com
PING B.test.com (10.1.128.76) 56(84) bytes of data.
64 bytes from A.test.com (10.1.128.76): icmp_seq=1 ttl=62 time=4.85 ms
64 bytes from A.test.com (10.1.128.76): icmp_seq=2 ttl=62 time=5.44 ms
但是,当我为该IP地址的PTR记录执行dig时,会显示不同的主机名:
; <<>> DiG 9.11.3-1ubuntu1.13-Ubuntu <<>> -x 10.1.128.76
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 42254
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;76.128.1.10.in-addr.arpa. IN PTR
;; ANSWER SECTION:
76.128.1.10.in-addr.arpa. 3600 IN PTR B.test.com
;; Query time: 0 msec
;; SERVER: 10.1.129.9#53(10.1.129.9)
;; WHEN: Sat Sep 19 22:41:59 HKT 2020
;; MSG SIZE rcvd: 87
;挖掘9.11.3-1ubuntu1.13-Ubuntu-x10.1.128.76
;; 全局选项:+cmd
;; 得到答案:
;; ->>头它来自直接DNS查找ping
向解析器询问主机B.test.com
的IP地址,并获取10.1.128.76
<代码>ping
不使用反向查找
我可以猜测在test.com
区域中有以下记录
A A 10.1.128.76
B A 10.1.128.76
或
在反向区域128.1.10.in-addr.arpa
76 IN PTR A.example.com.
这里是另一个示例(省略IP V6结果)
$host www.google.com
www.google.com的地址是172.217.5.100
$dig-x172.217.5.100
; 挖掘9.10.6-x172.217.5.100
;; 全局选项:+cmd
;; 得到答案:
;; ->>后来我发现主机文件将IP 10.1.128.76映射到A.test.com,而DNS将B.test.com解析到10.1.128.76。导致了这种奇怪的行为。
76 IN PTR A.example.com.
$host www.google.com
www.google.com has address 172.217.5.100
$dig -x 172.217.5.100
; <<>> DiG 9.10.6 <<>> -x 172.217.5.100
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 16073
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;100.5.217.172.in-addr.arpa. IN PTR
;; ANSWER SECTION:
100.5.217.172.in-addr.arpa. 21457 IN PTR sfo03s07-in-f4.1e100.net.
100.5.217.172.in-addr.arpa. 21457 IN PTR sfo03s07-in-f100.1e100.net.
;; Query time: 13 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sat Sep 19 23:28:06 PDT 2020
;; MSG SIZE rcvd: 124