Specifications

DS300f G2 Series User Manual
183
Chapter 7: teChnoloGy baCkGround
This chapter covers the following topics:
• "Disk Arrays" on page 183
• "Logical Drives" on page 184
• "Spare Drives" on page 193
• "RAID Controllers" on page 194
• "iSCSI Management" on page 197
• "Internet Protocols" on page 200
dIsk arrays
Disk array technology includes:
• "Media Patrol" on page 183
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checkuncongured
drives.
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.