What Do I Do If a Restarted Notebook Instance Can Be Connected Only After I Locally Delete known_hosts?

To resolve this issue, set notebook parameters StrictHostKeyChecking no and UserKnownHostsFile=/dev/null in the local ssh config file.

Host roma-local-cpu
    HostName x.x.x.x # IP address
    Port 22522
    User ma-user
    IdentityFile C:/Users/my.pem
    StrictHostKeyChecking no
    ForwardAgent yes

Note: SSH logins are insecure because the known_hosts file will be ignored during the logins.