--knownhosts

When doing SCP and SFTP transfers, curl automatically checks a database containing identification for all hosts it has ever been used with to verify that the host it connects to is the same as previously. Host keys are stored in such a known hosts file. curl uses the ~/.ssh/known_hosts in the user's home directory by default.

This option lets a user specify a specific file to check the host against.

The known hosts check can be disabled with --insecure, but that makes the transfer insecure and is strongly discouraged.