下载windows版nmap ，下载后双机默认安装。

Download the Free Nmap Security Scanner for Linux/Mac/Windows

打开CMD ， 输入 cd C:\Program Files (x86)\Nmap

C:\Program Files (x86)\Nmap>ncat -z -v -u ntp.aliyun.com 123
Ncat: Version 7.80 ( https://nmap.org/ncat )
Ncat: Connected to 203.107.6.88:123.
Ncat: UDP packet sent successfully   #这里是成功的提示
Ncat: 1 bytes sent, 0 bytes received in 2.11 seconds.

C:\Program Files (x86)\Nmap>ncat -z -v -u localhost 162
Ncat: Version 7.80 ( https://nmap.org/ncat )
Ncat: Connected to ::1:162.
Ncat: 远程主机强迫关闭了一个现有的连接。 .  #这里是失败的提示