nslookup命令用于查询DNS的记录，查看域名解析是否正常，在网络故障的时候用来诊断网络问题。nslookup的用法相对来说还是蛮简单的，主要是下面的几个用法。
1、直接查询 ¶
这个可能大家用到最多，查询一个域名的A记录。
nslookup domain [dns-server]
如果没指定dns-server，用系统默认的dns服务器。下面是一个例子：
C:/Users/jackie>nslookup www.ezloo.com 8.8.8.8
Server: google-public-dns-a.google.com
Address: 8.8.8.8
Non-authoritative answer:
Name: www.ezloo.com
Address: 70.32.68.136
2、查询其他记录 ¶
直接查询返回的是A记录，我们可以指定参数，查询其他记录，比如AAAA、MX等。
nslookup -qt=type domain [dns-server]
其中，type可以是以下这些类型：
A 地址记录
AAAA 地址记录
AFSDB Andrew文件系统数据库服务器记录
ATMA ATM地址记录
CNAME 别名记录
HINFO 硬件配置记录，包括CPU、操作系统信息
ISDN 域名对应的ISDN号码
MB 存放指定邮箱的服务器
MG 邮件组记录
MINFO 邮件组和邮箱的信息记录
MR 改名的邮箱记录
MX 邮件服务器记录
NS 名字服务器记录
PTR 反向记录
RP 负责人记录
RT 路由穿透记录
SRV TCP服务器信息记录
TXT 域名对应的文本信息
X25 域名对应的X.25地址记录
例如：
C:/Users/jackie>nslookup -qt=mx ezloo.com 8.8.8.8
Server: google-public-dns-a.google.com
Address: 8.8.8.8
Non-authoritative answer:
ezloo.com MX preference = 10, mail exchanger = aspmx.l.google.com
ezloo.com MX preference = 20, mail exchanger = alt1.aspmx.l.google.com
ezloo.com MX preference = 30, mail exchanger = alt2.aspmx.l.google.com
ezloo.com MX preference = 40, mail exchanger = aspmx2.googlemail.com
ezloo.com MX preference = 50, mail exchanger = aspmx3.googlemail.com
3、查询更具体的信息 ¶
查询语法：
nslookup –d [其他参数] domain [dns-server]
只要在查询的时候，加上-d参数，即可查询域名的缓存。
C:/Users/jackie>nslookup -d www.ezloo.com
------------
Got answer:
HEADER:
opcode = QUERY, id = 1, rcode = NOERROR
header flags: response, want recursion, recursion avail.
questions = 1, answers = 1, authority records = 2, additional = 2
QUESTIONS:
196.134.191.60.in-addr.arpa, type = PTR, class = IN
ANSWERS:
-> 196.134.191.60.in-addr.arpa
name = tzdns1.tzptt.zj.cn
ttl = 11568 (3 hours 12 mins 48 secs)
AUTHORITY RECORDS:
-> 191.60.in-addr.arpa
nameserver = dns-noc.zjhzptt.net.cn
ttl = 11537 (3 hours 12 mins 17 secs)
-> 191.60.in-addr.arpa
nameserver = ns.zjnbptt.net.cn
ttl = 11537 (3 hours 12 mins 17 secs)
ADDITIONAL RECORDS:
-> dns-noc.zjhzptt.net.cn
internet address = 202.96.103.36
ttl = 11522 (3 hours 12 mins 2 secs)
-> ns.zjnbptt.net.cn
internet address = 202.96.104.18
ttl = 11522 (3 hours 12 mins 2 secs)
------------
Server: tzdns1.tzptt.zj.cn
Address: 60.191.134.196
------------
Got answer:
HEADER:
opcode = QUERY, id = 2, rcode = NOERROR
header flags: response, want recursion, recursion avail.
questions = 1, answers = 1, authority records = 2, additional = 0
QUESTIONS:
www.ezloo.com, type = A, class = IN
ANSWERS:
-> www.ezloo.com
internet address = 70.32.68.136
ttl = 2732 (45 mins 32 secs)
AUTHORITY RECORDS:
-> ezloo.com
nameserver = ns61.domaincontrol.com
ttl = 2365 (39 mins 25 secs)
-> ezloo.com
nameserver = ns62.domaincontrol.com
ttl = 2365 (39 mins 25 secs)
------------
Non-authoritative answer:
------------
Got answer:
HEADER:
opcode = QUERY, id = 3, rcode = NOERROR
header flags: response, want recursion, recursion avail.
questions = 1, answers = 0, authority records = 1, additional = 0
QUESTIONS:
www.ezloo.com, type = AAAA, class = IN
AUTHORITY RECORDS:
-> ezloo.com
ttl = 10800 (3 hours)
primary name server = ns61.domaincontrol.com
responsible mail addr = dns.jomax.net
serial = 2011032900
refresh = 28800 (8 hours)
retry = 7200 (2 hours)
expire = 604800 (7 days)
default TTL = 86400 (1 day)
------------
Name: www.ezloo.com
Address: 70.32.68.136
