"Clean up local collections" means these steps
- Generate a new initialSyncId (this is intended to uniquely identify the node)
- Replace the oplogTruncateAfterPoint document with the checkpointTimestamp from the latest backup cursor.
- Replace the local.replset.config document with the current configuration.
- Replace the minValid document with a document with Timestamp(0,1), t: -1.
- Remove local.replset.election, as this node has not participated in any elections.