Problem: Use SSH to connect the server as usual, then occur
The target server is re-format before, the authentication information has been changed. You have to delete the old authentication information in your computer first.
ssh-keygen -R (target server IP)
Go to the host key directory, in my case the directory is “C:\Users\paulck.ssh”. Find the known_hosts file, delete the line that contains target server IP.
(target server IP) ecdsa-sha2-nistp256 (RSA key)