Specifications

DS300f G2 Series User Manual
193
spare drIves
Spare drive technology includes:
• "Denition"onpage193
• "Options" on page 193
• "Requirements" on page 193
• "Transition" on page 193
DefInItIon
A spare drive is a physical drive that you designate to automatically replace the failed physical drive in a disk
array.
The general recommendation is to:
• Provide at least one spare drive for every 16 physical drives in the RAID system
• Congurethesparesasglobalrevertiblesparedrives
oPtIonS
There are several options you can specify for a spare drive:
• System Options
• Revertible
–Returnstoitssparedriveassignmentafteryoureplacethefailed
physicaldriveinthediskarrayandruntheTransitionfunction.
• Media Patrol–Bydefault,MediaPatrolrunsonsparedrivesunlessyoudisableit.
• Spare Type
• Global
–Canbeusedbyanydiskarray
• Dedicated–Canbeusedonlybytheassigneddiskarray
• Media Type (type of physical drive)
•
HardDiskDrive(HDD)
• SolidStateDrive(SSD)
requIrementS
The spare drive must:
• Have adequate capacity to replace the largest physical drive in your disk arrays.
• Be the same media type as the physical drives in your disk arrays.
A revertible spare drive requires:
• You to replace the failed physical drive in the disk array
• You to run the Transition function
tranSItIon
Transition is the process of replacing a revertible spare drive that is currently part of a disk array with an
unconguredphysicaldriveoranon-revertiblespare.Therevertiblesparedrivereturnstoitsoriginalstatus.In
order to run the Transition function, the spare drive must be revertible.
Inaddition,youmustspecifyanunconguredphysicaldriveofthesameorlargercapacityandsamemedia
type as the revertible spare drive.
running A trAnsition
The Transition feature enables you to specify “permanent” spare drives for your ASUS DS300f G2 subsystem.
Transition is the process of replacing a revertible spare drive that is currently part of a disk array with an
unconguredphysicaldriveoranon-revertiblespare.Therevertiblesparedrivereturnstoitsoriginalstatus.
Transition happens automatically when the following sequence of events takes place:
• You create a revertible spare drive. See “Creating a Spare Drive Manually” on page 102.
• A physical drive assigned to your disk array fails and the array goes critical or degraded.
• ASUS DS300f G2 automatically rebuilds your array to the revertible spare drive and the array becomes
functional again.
• You replace the failed physical drive with a new physical drive of equal or greater capacity.
• ASUS DS300f G2 automatically transitions (moves) the data from the revertible spare to the new physical
drive.
• The new physical drive becomes part of the array and the revertible spare drive returns to its original spare
status.
Transitionhappensmanuallywhenyouspecifyadifferentunconguredphysicaldrivetotransition(move)the