Symptoms
-
Migration using SSH key cannot be initialized with the error in Plesk > Tools & Settings > Migration and Transfer Manager:
Failed to check SSH connection to the source server 'source' (203.0.113.2): q must be exactly 160, 224, or 256 bits long
Cause
SSH keys required for the migration are not installed properly.
Resolution
Apply one of two possible solutions:
- Re-generate SSH keys.
To re-generate SSH keys:
- Connect to the target server via SSH.
- Re-configure SSH keys as per the guide: Migration Guide: Authentication by SSH (Linux) .
- Re-start the migration using the SSH keys authorization.
If the issue still persists, check that the files below have the same permissions on the target and on the source server:
# stat ~/ | grep Access | head -n1
# stat ~/.ssh | grep Access | head -n1
# stat ~/.ssh/authorized_keys | grep Access | head -n1
- Change the authorization method from SSH keys to User / password for migration.
To change the authorization method from ‘SSH keys’ to ‘User / password’:
- Log into Plesk.
- Go to Tools & Settings > Migration and Transfer manager.
- Finish the current migration session by clicking on the Finish Migration.
- Confirm clearing all settings.
- Press the Start a New Migration button to start a new migration session.
- Set Authorization as User / password and specify
rootuser’s password. - Adjust other settings.
- Press the Prepare migration button to start a new migration session.
