Linux DNS之dig利器

吕海峰

发布于 2018-04-03 14:59:45

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发布于 2018-04-03 14:59:45

文章被收录于专栏：BrianBrian

概述

在之前介绍过Linux DNS之nslookup工具，今天我学习了一个比nslookup更强大的工具，并且现在非常流行——Dig，它是一个专业DNS工具。

用法

直接在命令行输入dig，可以看到很多DNS详细的信息.相对于nslookup查询来说，可以通过下面命令格式： **dig @dnsserver name -t querytype

[lhf@lv-centos ~]$ dig baidu.com

; <<>> DiG 9.9.4-RedHat-9.9.4-38.el7_3.1 <<>> baidu.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 31419
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 5, ADDITIONAL: 5

;; QUESTION SECTION:
;baidu.com.			IN	A

;; ANSWER SECTION:
baidu.com.		600	IN	A	220.181.57.217
baidu.com.		600	IN	A	180.149.132.47
baidu.com.		600	IN	A	123.125.114.144
baidu.com.		600	IN	A	111.13.101.208

;; AUTHORITY SECTION:
baidu.com.		46078	IN	NS	ns2.baidu.com.
baidu.com.		46078	IN	NS	ns3.baidu.com.
baidu.com.		46078	IN	NS	ns4.baidu.com.
baidu.com.		46078	IN	NS	ns7.baidu.com.
baidu.com.		46078	IN	NS	dns.baidu.com.

;; Query time: 3 msec
;; SERVER: 219.238.164.7#53(219.238.164.7)
;; WHEN: 三 2月 15 20:37:01 CST 2017
;; MSG SIZE  rcvd: 261

可以看出输出的内容还是DNS信息即(域名、生存时间、类别、类型和值)。如果想查询NS类型，则：

[lhf@lv-centos ~]$ dig @8.8.8.8 brianlv.com -t NS

; <<>> DiG 9.9.4-RedHat-9.9.4-38.el7_3.1 <<>> @8.8.8.8 brianlv.com ns
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 46978
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;brianlv.com.			IN	NS

;; ANSWER SECTION:
brianlv.com.		86399	IN	NS	dns10.hichina.com.
brianlv.com.		86399	IN	NS	dns9.hichina.com.

;; Query time: 699 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: 三 2月 15 20:41:47 CST 2017
;; MSG SIZE  rcvd: 87

dig技巧

域名文件解析(多域名)

如何高效的查询域名，比如查询：baidu.com和yahoo.com的A类型的值？我们可以这样处理，把需要查询的域名放到文件中。通过-f参数来实现域名文件的查询。

[lhf@lv-centos ~]$ cat list 
baidu.com
yahoo.com
[lhf@lv-centos ~]$ dig -f list -t A

; <<>> DiG 9.9.4-RedHat-9.9.4-38.el7_3.1 <<>> baidu.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 22360
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 5, ADDITIONAL: 5

;; QUESTION SECTION:
;baidu.com.			IN	A

;; ANSWER SECTION:
baidu.com.		600	IN	A	220.181.57.217
baidu.com.		600	IN	A	123.125.114.144
baidu.com.		600	IN	A	180.149.132.47
baidu.com.		600	IN	A	111.13.101.208
;; Query time: 3 msec
;; SERVER: 219.238.164.7#53(219.238.164.7)
;; WHEN: 三 2月 15 20:48:33 CST 2017
;; MSG SIZE  rcvd: 261

; <<>> DiG 9.9.4-RedHat-9.9.4-38.el7_3.1 <<>> yahoo.com
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 52250
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 5, ADDITIONAL: 8

;; QUESTION SECTION:
;yahoo.com.			IN	A

;; ANSWER SECTION:
yahoo.com.		600	IN	A	206.190.36.45
yahoo.com.		600	IN	A	98.138.253.109
yahoo.com.		600	IN	A	98.139.183.24
;; Query time: 3 msec
;; SERVER: 219.238.164.7#53(219.238.164.7)
;; WHEN: 三 2月 15 20:48:33 CST 2017
;; MSG SIZE  rcvd: 329

反向解析

我们如果知道域名的A记录，如何反向查找域名的映射关系呢？我们通过-x参数实现反向解析。

[lhf@lv-centos ~]$ dig -x 180.149.132.47

; <<>> DiG 9.9.4-RedHat-9.9.4-38.el7_3.1 <<>> -x 180.149.132.47
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 48479
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;47.132.149.180.in-addr.arpa.	IN	PTR

;; AUTHORITY SECTION:
132.149.180.in-addr.arpa. 2646	IN	SOA	idc-ns1.bjtelecom.net. wang_ye.bjxywh.com. 1348929128 10800 3600 604800 38400

;; Query time: 3 msec
;; SERVER: 219.238.164.7#53(219.238.164.7)
;; WHEN: 三 2月 15 20:56:08 CST 2017
;; MSG SIZE  rcvd: 131