SSH
Force Client to Use Password Authentication
Key authentication should always be setup, but sometimes it is necessary to authenticate using passwords—even if for nothing else than to verify passwords are disabled.
ssh -o PreferredAuthentications=password -o PubkeyAuthentication=no user@domain.com
Connect Without StrictHostKeyChecking (known_hosts)
Connects to a host without validating the host key using ~/.ssh/known_hosts or adding the key to that file.
ssh -o "StrictHostKeyChecking no" user@host