Dell UCPA-901, UCSE-900, UCSA-901, UCSB-900, UCPB-900, and UCPE-900 Reconfiguration of virtual disks

Reconfiguration of virtual disks

An online virtual disk can be reconfigured in ways that expands its capacity and/or change its RAID level.

NOTE: Spanned virtual disks such as RAID 10, 50, and 60 cannot be reconfigured.

NOTE: Reconfiguring Virtual Disks typically impacts disk performance until the reconfiguration operation is complete.

Online Capacity Expansion (OCE) can be done in two ways:

•If there is a single virtual disk in a disk group and free space is available, the virtual disk’s capacity can be expanded within that free space.

•If a virtual disk is created and it does not use the maximum size of the disk group, free space is available.

Free space is also available when a disk group’s physical disks are replaced by larger disks using the Replace Member feature. A virtual disk's capacity can also be expanded by performing an OCE operation to add more physical disks.

RAID Level Migration (RLM) refers to changing a virtual disk’s RAID level. Both RLM and OCE can be done at the same time so that a virtual disk can simultaneously have its RAID level changed and its capacity increased. When a RLM/OCE operation is complete, a reboot is not required. The source RAID level column indicates the virtual disk RAID level before the RLM/OCE operation and the target RAID level column indicates the RAID level after the RLM/OCE operation.

NOTE: If the controller already contains the maximum number of virtual disks, you cannot perform a RAID level migration or capacity expansion on any virtual disk.

NOTE: The controller changes the write cache policy of all virtual disks undergoing a RLM/OCE operation to Write-Through until the RLM/OCE operation is complete.

See the following table for a list of RLM/OCE possibilities.

Table 2. RAID level migration

Source RAID	Target RAID	Number of	Number of	Capacity	Description
Level	Level	Physical Disks	Physical Disks	Expansion
		(Beginning)	(End)	Possible
RAID 0	RAID 0	1	2 or more	Yes	Increases
					capacity by
					adding disks.
RAID 0	RAID 1	1	2	No	Converts a
					non-redundant
					virtual disk into
					a mirrored
					virtual disk by
					adding one
					disk.
RAID 0	RAID 5	1 or more	3 or more	Yes	At least one
					disk needs to
					be added for

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