We can ping ordinary websites, such as Taobao Sina and other websites, and a few websites restrict ping;

Then we ping the port of the website, and the default is generally 80. Our ppinging tool is tcping based on 80.

Some websites we open are ip addresses and port numbers. Generally, this kind of address can be pinged, but some can't, such as this one, and the ping test function has been turned off;

We can't ping ip and port number directly.

We can ping the destination address and add the port number using the tcping gadget. The tcping widget is placed in the same location as the system ping tool;

TCP-ing gadgets can be downloaded from the Internet, and the directory is here. If it is not downloaded or put in the wrong directory, it is an invalid TCP-ing command.