SSH connection error in Ubuntu: WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED

SSH connection error in Ubuntu: WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED

There is a problem : When configuring the hadoop experimental environment, when configuring each node for SSH password-free login, and using the node21 node to connect to the master2 node through SSH,the error WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED occurred.

Cause of the problem: Ping the master2 node and find that the network is normal. By searching, it is found that the information in the file known_hosts under the .ssh file has changed.

Solution: delete the content in know_hosts, save, and exit.