Windows
The property "filesystemcrawler.mount.drive.validletters.windows" in the \Program Files\Symantec\DataLossPrevention\DetectionServer\16.0.00000\Protect\config\Crawler.properties file defines the available drives.. This value lists all the valid drive letters that can be used to mount a share on windows. If multiple filesystems scans are running simultaneously on a server, each share will be mounted on a drive letter specified in the property.

Linux

If multiple filesystems scans are running simultaneously on a server, the share will be mounted on  "filesystemcrawler.mount.drive.letter.linux"/scanAssignmentId.  The setting is also defined in the crawler.properties file. The directory will be created automatically if required.