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Promise Technology
Pegasus3 R4/R6/R8
Disk Arrays
Disk array technology includes:
• Media Patrol
• PDM
Media Patrol
Media Patrol is a routine maintenance procedure that checks the magnetic media on each disk drive.
Media Patrol checks all physical drives assigned to disk arrays and spare drives. Media Patrol does not
checkuncongureddrives.
Media Patrol checks are enabled by default on all disk arrays and spare drives. You can disable Media
Patrol in the disk array and spare drive settings, however that action is not recommended.
Unlike Synchronization and Redundancy Check, Media Patrol is concerned with the condition of the
media itself, not the data recorded on the media. If Media Patrol encounters a critical error, it triggers
PDM, if PDM is enabled on the disk array.
Media Patrol has three status conditions:
• Running– Normal. You can access your logical drives at any time.
• Yield– Temporary pause while a read/write operation takes place.
• Paused– Temporary pause while another background runs. Or a pause initiated by the user.
See “Media Patrol” on page 85.