Users Guide

3. From Action drop-down menu, select an action.
When you select an action, an additional Action window displayed. Select / enter the desired value.
• Rename
• Delete
• Edit Cache Policy — You can change the cache policy for the following options:
• Read Policy — Following values are available for selection:
• Adaptive Read Ahead — Indicates that for the given volume, the control uses the Read-Ahead cache policy if the two
most recent disks accesses occurred in sequential sectors. If the read requests are random, the controller returns to No
Read Ahead mode.
• No Read Ahead — Indicates that for the given volume, no read ahead policy is used.
• Read Ahead — Indicates that for the given volume, the controller reads sequentially ahead of the requested data and
stores the additional data in cache memory, anticipating a data requirement. This speeds up sequential data reads, but
there is less improvement when accessing random data.
• Write Policy — Change the write cache policy to one of the following options:
• Write Through — Indicates that for the given volume, the controller sends a data transfer completion signal to the host
system when the disk subsystem has received all the data in a transaction.
• Write Back — Indicates that for the given volume, the controller sends a data transfer completion signal to the host
system when the controller cache has received all the data in a transaction. The controller then writes the cached data to
the storage device in the background.
• Force Write Back — When using force write-back caching, the write cache is enabled regardless of whether the
controller has a battery. If the controller does not have a battery and force write-back caching is used, data loss may occur
in the event of a power failure.
• Disk Cache Policy — Change the disk cache policy to one of the following options:
• Default — Indicates that the disk is using its default write cache mode. For SATA disks, this is enabled and for SAS disks
this is disabled.
• Enabled — Indicates that the disk’s write cache is enabled. This increases performance and the probability of data loss if
there is power loss.
• Disabled — Indicates that the disk’s write cache is disabled. This decreases performance and the probability of data loss.
• Edit Disk Capacity — You can add the physical disks to the selected virtual disk in this window. This window also shows the
current capacity and new capacity of the virtual disk after adding the physical disks.
• RAID Level Migration — Displays the Disk Name, Current RAID Level, and size of the virtual disk. Allows you to select a New
RAID Level. User may have to add additional drives to existing Virtual disks to migrate to new raid level. This feature is not
applicable on RAID 10, 50 and 60.
• Initialize: Fast — Updates the metadata on the physical disks so that all the disk space is available for future write operations.
The initialize option can be completed quickly because existing information on the physical disks is not erased, although future write
operations overwrites any information that remains on the physical disks.
• Initialize: Full — All existing data and file systems are erased.
NOTE: The Initialize: Full option is not applicable for PERC H330 controllers.
• Check Consistency — To check the consistency of a virtual disk, select Check Consistency from the corresponding drop-
down menu.
NOTE: Consistency check is not supported on drives set up in RAID0 mode.
For more information about these options, see the iDRAC Online Help.
4. Click Apply Now to apply the changes immediately, At Next Reboot to apply the changes after next reboot, At Scheduled Time to
apply the changes at a particular time, and Discard All Pending to discard the changes.
Based on the selected operation mode, the settings are applied.
Managing virtual disks using RACADM
Use the following commands to manage virtual disks:
• To delete virtual disk:
racadm storage deletevd:<VD FQDD>
• To initialize virtual disk:
racadm storage init:<VD FQDD> -speed {fast|full}
Managing storage devices
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