TCP和UDP端口测试

我们测试电脑网是否正常的时候习惯用ping,但ping是基于ICMP协议,所认它并不能检测TCP或UDP端口是否正常。

telnet命令

在linux和win中都可以用telnet命令来测试TCP的端口是否正常。

linux下安装

yum install -y telnet

win下安装

进入 控制面板-> 所有控制面板项 -> 程序和功能 -> 启用或关闭Windows功能,找到 Telnet Client并开启

使用

telnet IP/域名 port

[root@zngw ~]# telnet zengwu.com.cn 80
Trying 8.141.190.210...
Connected to zengwu.com.cn.
Escape character is '^]'.
^CConnection closed by foreign host.

说明zengwu.com.cn的80端口是联通的

nc命令

linux下安装

yum install -y nc

win下安装

win下需要下载netcat运行程序https://eternallybored.org/misc/netcat/

下载后直接解压,将nc.exe复制到C:\Windows\System32目录或装nc.exe添加到系统path环境变量中

使用

测试TCP

nc -vz IP/域名 port

[root@zngw ~]# nc -vz zengwu.com.cn 80
Ncat: Version 7.50 ( https://nmap.org/ncat )
Ncat: Connected to 8.141.190.210:80.
Ncat: 0 bytes sent, 0 bytes received in 0.04 seconds.

测试UDP

nc -vuz IP/域名 port

[root@qy ~]# nc -vuz zengwu.com.cn 5000
Ncat: Version 7.50 ( https://nmap.org/ncat )
Ncat: Connected to 8.141.190.210:80:5000.
Ncat: UDP packet sent successfully
Ncat: 1 bytes sent, 0 bytes received in 0.11 seconds.
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