If the platform's public SSH key is not specified on the external storage, VM backups will not be written to that storage. To check the key:
- Connect to the server with the platform via SSH.
- Copy or save the public platform key from the ~/.ssh/id_rsa.pub file.
- Connect to the external storage via SSH. Use the login and port specified in the storage connection settings.
- Check the contents of the public key in the ~/.ssh/authorized_keys file.
- If the content of the key does not match the platform's public key, delete the wrong key and add the correct one.