source Server Resource Id
  The source server resource ID to restore from. It's required when 'createMode' is 'PointInTimeRestore' or 'GeoRestore' or 'Replica'. This property is returned only for Replica server
The source server resource ID to restore from. It's required when 'createMode' is 'PointInTimeRestore' or 'GeoRestore' or 'Replica'. This property is returned only for Replica server