bash - Quick way to find if a port is open on Linux - Stack Overflow

bash - Quick way to find if a port is open on Linux - Stack Overflow

You can use netcat for this.

nc ip port < /dev/null

connects to the server and directly closes the connection again. If netcat is not able to connect, it returns a non-zero exit code. The exit code is stored in the variable $?. As an example,

nc ip port < /dev/null; echo $?

will return 0 if and only if netcat could successfully connect to the port.

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