nc

Netcat(or nc) is a command-line utility that reads and write data across network connections, using the TCP or UDP protocols. It is one of the most powerful tools in the network and system administrators arsenal, and it as considered as a Swiss army knife of networking tools.

Netcat is cross-platform, and it’s available for Linux, macOS, Windows , and BSD. You can use Netcat to debug and monitor network connections, scan for open ports, transfer data, as a proxy and more.

The Netcat package is pre-installed on macOS and popular Linux distributions like Ubuntu, Debian or CentOS.

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Reference

https://linuxize.com/post/netcat-nc-command-with-examples/

telnet 命令

测试某个端口是否通

nc 命令

nc的全名是netcat，其主要用途是建立和监听任意TCP和UDP连接，支持ipv4和ipv6。因此，它可以用来网络调试、端口扫描等等。