10 Linux DIG Command Examples for DNS Lookup--reference
by RAMESH NATARAJAN on FEBRUARY 29, 2012
http://www.thegeekstuff.com/2012/02/dig-command-examples/
Dig stands for domain information groper.
Using dig command you can query DNS name servers for your DNS lookup related tasks. This article explains 10 examples on how to use dig command.
1. Simple dig Command Usage (Understand dig Output)
When you pass a domain name to the dig command, by default it displays the A record (the ip-address of the site that is queried) as shown below.
In this example, it displays the A record of redhat.com in the “ANSWER SECTION” of the dig command output.
$ dig redhat.com ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> redhat.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62863
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 3 ;; QUESTION SECTION:
;redhat.com. IN A ;; ANSWER SECTION:
redhat.com. 37 IN A 209.132.183.81 ;; AUTHORITY SECTION:
redhat.com. 73 IN NS ns4.redhat.com.
redhat.com. 73 IN NS ns3.redhat.com.
redhat.com. 73 IN NS ns2.redhat.com.
redhat.com. 73 IN NS ns1.redhat.com. ;; ADDITIONAL SECTION:
ns1.redhat.com. 73 IN A 209.132.186.218
ns2.redhat.com. 73 IN A 209.132.183.2
ns3.redhat.com. 73 IN A 209.132.176.100 ;; Query time: 13 msec
;; SERVER: 209.144.50.138#53(209.144.50.138)
;; WHEN: Thu Jan 12 10:09:49 2012
;; MSG SIZE rcvd: 164
The dig command output has the following sections:
- Header: This displays the dig command version number, the global options used by the dig command, and few additional header information.
- QUESTION SECTION: This displays the question it asked the DNS. i.e This is your input. Since we said ‘dig redhat.com’, and the default type dig command uses is A record, it indicates in this section that we asked for the A record of the redhat.com website
- ANSWER SECTION: This displays the answer it receives from the DNS. i.e This is your output. This displays the A record of redhat.com
- AUTHORITY SECTION: This displays the DNS name server that has the authority to respond to this query. Basically this displays available name servers of redhat.com
- ADDITIONAL SECTION: This displays the ip address of the name servers listed in the AUTHORITY SECTION.
- Stats section at the bottom displays few dig command statistics including how much time it took to execute this query
2. Display Only the ANSWER SECTION of the Dig command Output
For most part, all you need to look at is the “ANSWER SECTION” of the dig command. So, we can turn off all other sections as shown below.
- +nocomments – Turn off the comment lines
- +noauthority – Turn off the authority section
- +noadditional – Turn off the additional section
- +nostats – Turn off the stats section
- +noanswer – Turn off the answer section (Of course, you wouldn’t want to turn off the answer section)
The following dig command displays only the ANSWER SECTION.
$ dig redhat.com +nocomments +noquestion +noauthority +noadditional +nostats ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> redhat.com +nocomments +noquestion +noauthority +noadditional +nostats
;; global options: +cmd
redhat.com. 9 IN A 209.132.183.81
Instead of disabling all the sections that we don’t want one by one, we can disable all sections using +noall (this turns off answer section also), and add the +answer which will show only the answer section.
The above command can also be written in a short form as shown below, which displays only the ANSWER SECTION.
$ dig redhat.com +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> redhat.com +noall +answer
;; global options: +cmd
redhat.com. 60 IN A 209.132.183.81
3. Query MX Records Using dig -t MX
To query MX records, pass MX as an argument to the dig command as shown below.
$ dig redhat.com MX +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> redhat.com MX +noall +answer
;; global options: +cmd
redhat.com. 513 IN MX 5 mx1.redhat.com.
redhat.com. 513 IN MX 10 mx2.redhat.com.
You can also use option -t to pass the query type (for example: MX) as shown below.
$ dig -t MX redhat.com +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> -t MX redhat.com +noall +answer
;; global options: +cmd
redhat.com. 489 IN MX 10 mx2.redhat.com.
redhat.com. 489 IN MX 5 mx1.redhat.com.
4. Query NS Records Using dig -t NS
To query the NS record use the type NS as shown below.
$ dig redhat.com NS +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> redhat.com NS +noall +answer
;; global options: +cmd
redhat.com. 558 IN NS ns2.redhat.com.
redhat.com. 558 IN NS ns1.redhat.com.
redhat.com. 558 IN NS ns3.redhat.com.
redhat.com. 558 IN NS ns4.redhat.com.
You can also use option -t to pass the query type (for example: NS) as shown below.
$ dig -t NS redhat.com +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> -t NS redhat.com +noall +answer
;; global options: +cmd
redhat.com. 543 IN NS ns4.redhat.com.
redhat.com. 543 IN NS ns1.redhat.com.
redhat.com. 543 IN NS ns3.redhat.com.
redhat.com. 543 IN NS ns2.redhat.com.
5. View ALL DNS Records Types Using dig -t ANY
To view all the record types (A, MX, NS, etc.), use ANY as the record type as shown below.
$ dig redhat.com ANY +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> redhat.com ANY +noall +answer
;; global options: +cmd
redhat.com. 430 IN MX 5 mx1.redhat.com.
redhat.com. 430 IN MX 10 mx2.redhat.com.
redhat.com. 521 IN NS ns3.redhat.com.
redhat.com. 521 IN NS ns1.redhat.com.
redhat.com. 521 IN NS ns4.redhat.com.
redhat.com. 521 IN NS ns2.redhat.com.
(or) Use -t ANY
$ dig -t ANY redhat.com +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> -t ANY redhat.com +noall +answer
;; global options: +cmd
redhat.com. 367 IN MX 10 mx2.redhat.com.
redhat.com. 367 IN MX 5 mx1.redhat.com.
redhat.com. 458 IN NS ns4.redhat.com.
redhat.com. 458 IN NS ns1.redhat.com.
redhat.com. 458 IN NS ns2.redhat.com.
redhat.com. 458 IN NS ns3.redhat.com.
6. View Short Output Using dig +short
To view just the ip-address of a web site (i.e the A record), use the short form option as shown below.
$ dig redhat.com +short
209.132.183.81
You can also specify a record type that you want to view with the +short option.
$ dig redhat.com ns +short
ns2.redhat.com.
ns3.redhat.com.
ns1.redhat.com.
ns4.redhat.com.
7. DNS Reverse Look-up Using dig -x
To perform a DNS reverse look up using the ip-address using dig -x as shown below
For example, if you just have an external ip-address and would like to know the website that belongs to it, do the following.
$ dig -x 209.132.183.81 +short
www.redhat.com.
To view the full details of the DNS reverse look-up, remove the +short option.
$ dig -x 209.132.183.81 ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> -x 209.132.183.81
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62435
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 3 ;; QUESTION SECTION:
;81.183.132.209.in-addr.arpa. IN PTR ;; ANSWER SECTION:
81.183.132.209.in-addr.arpa. 600 IN PTR www.redhat.com. ;; AUTHORITY SECTION:
183.132.209.in-addr.arpa. 248 IN NS ns2.redhat.com.
183.132.209.in-addr.arpa. 248 IN NS ns1.redhat.com.
183.132.209.in-addr.arpa. 248 IN NS ns3.redhat.com.
183.132.209.in-addr.arpa. 248 IN NS ns4.redhat.com. ;; ADDITIONAL SECTION:
ns1.redhat.com. 363 IN A 209.132.186.218
ns2.redhat.com. 363 IN A 209.132.183.2
ns3.redhat.com. 363 IN A 209.132.176.100 ;; Query time: 35 msec
;; SERVER: 209.144.50.138#53(209.144.50.138)
;; WHEN: Thu Jan 12 10:15:00 2012
;; MSG SIZE rcvd: 193
8. Use a Specific DNS server Using dig @dnsserver
By default dig uses the DNS servers defined in your /etc/resolv.conf file.
If you like to use a different DNS server to perform the query, specify it in the command line as @dnsserver.
The following example uses ns1.redhat.com as the DNS server to get the answer (instead of using the DNS servers from the /etc/resolv.conf file).
$ dig @ns1.redhat.com redhat.com ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> @ns1.redhat.com redhat.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 20963
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 4
;; WARNING: recursion requested but not available ;; QUESTION SECTION:
;redhat.com. IN A ;; ANSWER SECTION:
redhat.com. 60 IN A 209.132.183.81 ;; AUTHORITY SECTION:
redhat.com. 600 IN NS ns1.redhat.com.
redhat.com. 600 IN NS ns4.redhat.com.
redhat.com. 600 IN NS ns3.redhat.com.
redhat.com. 600 IN NS ns2.redhat.com. ;; ADDITIONAL SECTION:
ns1.redhat.com. 600 IN A 209.132.186.218
ns2.redhat.com. 600 IN A 209.132.183.2
ns3.redhat.com. 600 IN A 209.132.176.100
ns4.redhat.com. 600 IN A 209.132.188.218 ;; Query time: 160 msec
;; SERVER: 209.132.186.218#53(209.132.186.218)
;; WHEN: Thu Jan 12 10:22:11 2012
;; MSG SIZE rcvd: 180
9. Bulk DNS Query Using dig -f (and command line)
Query multiple websites using a data file:
You can perform a bulk DNS query based on the data from a file.
First, create a sample names.txt file that contains the website that you want to query.
$ vi names.txt
redhat.com
centos.org
Next, execute dig -f as shown below, which will perform DNS query for the websites listed in the names.txt file and display the output.
$ dig -f names.txt +noall +answer
redhat.com. 60 IN A 209.132.183.81
centos.org. 60 IN A 72.232.194.162
You can also combine record type with the -f option. The following example displays the MX records of multiple websites that are located in the names.txt file.
$ dig -f names.txt MX +noall +answer
redhat.com. 600 IN MX 10 mx2.redhat.com.
redhat.com. 600 IN MX 5 mx1.redhat.com.
centos.org. 3600 IN MX 10 mail.centos.org.
Query multiple websites from dig command line:
You can also query multiple websites from the dig command line as shown below. The following example queries MX record for redhat.com, and NS record for centos.org from the command line
$ dig redhat.com mx +noall +answer centos.org ns +noall +answer ; <<>> DiG 9.7.3-RedHat-9.7.3-2.el6 <<>> redhat.com mx +noall +answer centos.org ns +noall +answer
;; global options: +cmd
redhat.com. 332 IN MX 10 mx2.redhat.com.
redhat.com. 332 IN MX 5 mx1.redhat.com.
centos.org. 3778 IN NS ns3.centos.org.
centos.org. 3778 IN NS ns4.centos.org.
centos.org. 3778 IN NS ns1.centos.org.
10. Use $HOME/.digrc File to Store Default dig Options
If you are always trying to view only the ANSWER section of the dig output, you don’t have to keep typing “+noall +answer” on your every dig command. Instead, add your dig options to the .digrc file as shown below.
$ cat $HOME/.digrc
+noall +answer
Now anytime you execute dig command, it will always use +noall and +answer options by default. Now the dig command line became very simple and easy to read without you have to type those options every time.
$ dig redhat.com
redhat.com. 60 IN A 209.132.183.81 $ dig redhat.com MX
redhat.com. 52 IN MX 5 mx1.redhat.com.
redhat.com. 52 IN MX 10 mx2.redhat.com.
Linux provides several powerful administrative tools and utilities which will help you to manage your systems effectively. If you don’t know what these tools are and how to use them, you could be spending lot of time trying to perform even the basic administrative tasks. The focus of this course is to help you understand system administration tools, which will help you to become an effective Linux system administrator
10 Linux DIG Command Examples for DNS Lookup--reference的更多相关文章
- 15 Linux Split and Join Command Examples to Manage Large Files--reference
by HIMANSHU ARORA on OCTOBER 16, 2012 http://www.thegeekstuff.com/2012/10/15-linux-split-and-join-co ...
- 18 Tar Command Examples in Linux
FROM: http://www.tecmint.com/18-tar-command-examples-in-linux/ 18 Tar Command Examples in Linux By R ...
- 12 Linux Which Command, Whatis Command, Whereis Command Examples
This Linux tutorial will explain the three "W" commands. The three "W"s are what ...
- 15 Basic ‘ls’ Command Examples in Linux
FROM: http://www.tecmint.com/15-basic-ls-command-examples-in-linux/ ls command is one of the most fr ...
- 15 Practical Grep Command Examples In Linux / UNIX
You should get a grip on the Linux grep command. This is part of the on-going 15 Examples series, wh ...
- linux环境，无dig命令-bash: dig: command not found？
背景描述: 今天使用dig命令,报错命令不存在,-bash: dig: command not found 解决: 通过yum方式安装 yum -y install bind-utils 备注:之前尝 ...
- Top 30 Nmap Command Examples For Sys/Network Admins
Nmap is short for Network Mapper. It is an open source security tool for network exploration, securi ...
- Linux运维实战之DNS（bind）服务器的安装与配置
转自http://sweetpotato.blog.51cto.com/533893/1598225 上次博文我们讨论了DNS的基础,本次博文我们重点来看看如何配置一台DNS服务器. [本次博文的主要 ...
- Linux搭建基于BIND的DNS服务器
Linux搭建基于BIND的DNS服务器 实验目标: 通过本实验掌握基于Linux的DNS服务器搭建. 实验步骤: 1.安装BIND 2.防火墙放通DNS服务 3.编辑BIND的主配置文件 4.编 ...
随机推荐
- c# 两个字符串，s="aeiou",s2="welcome to Quantum Asia"
c# 两个字符串,s="aeiou",s2="welcome to Quantum Asia" 方案一: 使用while循环: static void Mai ...
- this指针------新标准c++程序设计
背景: c++是在c语言的基础上发展而来的,第一个c++的编译器实际上是将c++程序翻译成c语言程序,然后再用c语言编译器进行编译.c语言没有类的概念,只有结构,函数都是全局函数,没有成员函数.翻 ...
- 计算机基础知识和tcp详解
计算机基础知识 作为应用软件开发程序员是写应用软件的,而应用软件必须应用在操作系统之上,调用操作系统接口,由操作系统控制硬件 比如客户端软件想要基于网络发送一条消息给服务端软件,流程是: 1.客户端软 ...
- [Swift实际操作]九、完整实例-(1)在iTunesConnect网站中创建产品
本文将通过一个实例项目,演示移动应用开发的所有步骤.首先要做的是打开浏览器,并进入[iTunesConnect网站],需要通过它创建一款自己的应用. 在iTunesConnect的登录页面中,输入自己 ...
- avascript的匿名函数
一.什么是匿名函数? 在Javascript定义一个函数一般有如下三种方式: 函数关键字(function)语句: function fnMethodName(x){alert(x);} 函数字面量( ...
- python3+Django1.11+mysql5.7 MySQL DB API Drivers
The Python Database API is described in PEP 249. MySQL has three prominent drivers that implement th ...
- AJAX发送json，SpringMVC 接收JSON，@RequestBody
需求:JQuery ajax前台,采用 POST请求 发送json,后台使用SpringMVC接收json并处理 前台: $.ajax({ url:"请求地址", type:&qu ...
- (原創) Gvim 個人習慣常用設定 (vim)
不定期更新這篇,因為查詢到好用的設定或者插件就會更新自己的設定. "set nocompatible let $LANG='zh_TW.UTF-8' set langmenu=zh_tw.u ...
- Android Studio 常用应用
1.在控制台的Logcat中输出测试语句 package com.example.lucky.helloworld; import android.support.v7.app.AppCompatAc ...
- python学习，day2：python字符串和二进制之间的互换
在python3中,byte二进制和striing字符串之间不能直接操作,需要进行编码和解码才行.下面是个例子 msg = '我爱北京天安门' print(msg) print(msg.encode( ...