Record Date: at 13:52 on the June 21, 2019
Operating System: Windows 10
Since the Ping command to check whether the network connectivity, but can not accurately determine whether a port connectivity, it is necessary to use the Telnet protocol.
1, and functions to open the control program panel.
2, sidebar, enable or disable Windows features.
3, check the Telnet client, click OK.
use:
1, the test port is open
Open a command prompt, enter telnet ip port, Enter.
Shown below, the port is not open, or not accessible, and access is denied. You need to check the firewall application.
C: \ Users \ Curre> telnet 127.0.0.1 8080
Connecting 127. 0.0.1 ... Could not open connection to the host. In the port 8080: Connect failed
Reproduced in: https: //www.cnblogs.com/Currention/p/11064502.html