It took a long time. I once felt that I was not suitable for learning technology, and I couldn’t even make the configuration. But it’s okay.

One reason: check whether SSH is installed. Command: SSH localhost

Solution: it is more convenient to check this blog post than to find other sources. https://www.cnblogs.com/cyyz-le/p/11780246.html

Reason 2: check whether the login name is correct. I fell here. A very speechless mistake.

Solution: look at the picture.