文章目录
- 1.命令简介
- 2.命令格式
- 3.选项说明
- 4.常用示例
- 参考文献
1.命令简介
host 是常用的域名解析工具，可以用来测试域名系统工作是否正常。
host 命令是一个用于执行 DNS 查找的简单实用程序。它通常用于将名称转换为 IP 地址，反之亦然。
2.命令格式
代码语言：javascript复制host
host [-aCdlnrsTwv] [-c class] [-N ndots] [-R number] [-t type] [-W wait] [-m flag] [-4] [-6] <name> [server]如果没有给出参数或选项，host 将打印其命令行参数和选项的简短说明。
3.选项说明
代码语言：javascript复制-a
显示详细的 DNS 信息。
-c <class>
指定查询类型，默认值为 IN（Internet）。
-C
查询指定主机的完整的 SOA 记录。
-r
不使用递归的查询方式查询域名。
-t <type>
指定查询的域名信息类型。
-v
显示指令执行的详细信息
-w
如果域名服务器没有给出应答信息，则总是等待，直到域名服务器给出应答。
-W <wait>
指定域名查询的最长时间，如果在指定时间内域名服务器没有给出应答信息则退出。
-4
使用 IPv4 查询传输 （默认）。
-6
使用 IPv6 查询传输。4.常用示例
（1）打印其命令行参数和选项的简短说明。
代码语言：javascript复制host
Usage: host [-aCdilrTvVw] [-c class] [-N ndots] [-t type] [-W time]
[-R number] [-m flag] hostname [server]
-a is equivalent to -v -t ANY
-c specifies query class for non-IN data
-C compares SOA records on authoritative nameservers
-d is equivalent to -v
-i IP6.INT reverse lookups
-l lists all hosts in a domain, using AXFR
-m set memory debugging flag (trace|record|usage)
-N changes the number of dots allowed before root lookup is done
-r disables recursive processing
-R specifies number of retries for UDP packets
-s a SERVFAIL response should stop query
-t specifies the query type
-T enables TCP/IP mode
-v enables verbose output
-V print version number and exit
-w specifies to wait forever for a reply
-W specifies how long to wait for a reply
-4 use IPv4 query transport only
-6 use IPv6 query transport only（2）查询域名对应的 IP 地址。
代码语言：javascript复制host www.baidu.com
www.baidu.com is an alias for www.a.shifen.com.
www.a.shifen.com has address 110.242.68.4
www.a.shifen.com has address 110.242.68.3（3）显示执行域名查询的详细信息。
代码语言：javascript复制host -v www.baidu.com
Trying "www.baidu.com"
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 59291
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;www.baidu.com. IN A
;; ANSWER SECTION:
www.baidu.com. 143 IN CNAME www.a.shifen.com.
www.a.shifen.com. 121 IN A 220.181.38.149
www.a.shifen.com. 121 IN A 220.181.38.150
Received 90 bytes from 183.60.83.19#53 in 0 ms
Trying "www.a.shifen.com"
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45319
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUESTION SECTION:
;www.a.shifen.com. IN AAAA
;; AUTHORITY SECTION:
a.shifen.com. 490 IN SOA ns1.a.shifen.com. baidu_dns_master.baidu.com. 2211020024 5 5 2592000 3600
Received 97 bytes from 183.60.83.19#53 in 0 ms
Trying "www.a.shifen.com"
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27410
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0
;; QUESTION SECTION:
;www.a.shifen.com. IN MX
;; AUTHORITY SECTION:
a.shifen.com. 376 IN SOA ns1.a.shifen.com. baidu_dns_master.baidu.com. 2211020024 5 5 2592000 3600
Received 97 bytes from 183.60.83.19#53 in 0 ms（4）查询域名的 MX 信息。
代码语言：javascript复制host -t MX www.baidu.com
www.baidu.com is an alias for www.a.shifen.com.
www.a.shifen.com is an alias for www.wshifen.com.（5）显示详细的 DNS 信息。
代码语言：javascript复制host -a www.baidu.com
Trying "www.baidu.com"
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 11585
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;www.baidu.com. IN ANY
;; ANSWER SECTION:
www.baidu.com. 1122 IN CNAME www.a.shifen.com.（6）用谷歌的 DNS（8.8.8.8）来查百度主机的 IP。
代码语言：javascript复制host www.baidu.com 8.8.8.8
Using domain server:
Name: 8.8.8.8
Address: 8.8.8.8#53
Aliases:
www.baidu.com is an alias for www.a.shifen.com.
www.a.shifen.com has address 14.215.177.38
www.a.shifen.com has address 14.215.177.39
www.a.shifen.com is an alias for www.wshifen.com.参考文献
host(1) manual - linux.org
