Dell PowerEdge H730P, Руководство пользователя

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CAUTION: Do not attempt disk migration during RLM or online capacity expansion (OCE). This
causes loss of the virtual disk.
Migrating Virtual Disks
To migrate virtual disks from PERC H710, H710P, or H810 to PERC H730P:
1. Turn off the system.
2. Move the physical disks from PERC H710, H710P, or H810 card to the PERC H730P card.
3. Boot the system and import the foreign configuration that is detected. You can do one of the
following:
• Press <F> to automatically import the foreign configuration.
• Enter the
BIOS Configuration Utility and navigate to the Foreign Configuration View .
NOTE: For more information on accessing the BIOS Configuration Utility , see Entering The
BIOs Configuration Utility .
NOTE: For more information on Foreign Configuration View , see Foriegn Configuration View .
4. Exit the BIOS Configuration Utility and reboot the system.
5. Ensure that all the latest drivers for the PERC H710, H710P, or H810 card (available at dell.com/
support ) are installed.
For more information, see Driver Installation .
Virtual Disk Write Cache Policies
The write cache policy of a virtual disk determines how the controller handles writes to the virtual disk.
The write cache policies are:
Write-Back The controller sends a data transfer completion signal to the host 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.
NOTE: The default cache setting for virtual disks is Write-Back caching.
Write-Through The controller sends a data transfer completion signal to the host system when the
disk subsystem has received all the data in a transaction.
All RAID volumes are presented as
Write-Through to the operating system
(Windows and Linux) independent of the actual write cache policy of the virtual
disk. The PERC cards manage the data in cache independently of the operating
system or any applications.
NOTE: Certain data patterns and configurations perform better with a Write-
Through cache policy.
NOTE: Use the Dell OpenManage storage management application or the BIOS Configuration
Utility to view and manage virtual disk cache settings.
Conditions Under Which Write-Back Is Employed
Write-Back caching is used under all conditions in which the battery is present and in good condition.
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