Users Guide

Managing preserved cache
About this task
If a virtual disk goes offline or is deleted because of missing physical disks, the controller preserves the dirty cache from the virtual disk.
The preserved dirty cache, known as pinned cache, is preserved until you import the virtual disk or discard the cache.
NOTE: Certain operations, such as creating a new virtual disk, cannot be performed if preserved cache exists. You have
to enter the BIOS Configuration Utility (<Ctrl> <R>) to resolve the situation before you boot to the operating system.
Messages are displayed notifying you that you must enter the BIOS Configuration Utility (<Ctrl> <R>) to discard the
preserved cache or import the virtual disks with the preserved cache.
CAUTION: If there are any foreign configurations, it is strongly advised that you import the foreign configuration before
you discard the preserved cache. Otherwise, you might lose data that belongs with the foreign configuration.
To manage the preserved cache:
Steps
1. On the VD Mgmt screen, click on a controller icon.
2. Press <F2> to display the available actions.
3. Select Manage Preserved Cache.
A message is displayed advising you to import the foreign configuration before you discard the preserved cache to avoid losing data
belonging to the foreign configuration. Confirm whether you want to continue. The Manage Preserved Cache screen displays the
affected virtual disks.
4. You can choose to discard the cache on the Manage Preserved Cache screen. If you press Cancel, the process is cancelled and the
Preserved Cache Retained dialog box is displayed. If you choose to discard the cache, you are prompted to confirm your choice. If
you choose to retain the cache, a message is displayed to notify you that you cannot perform certain operations while the cache
exists. Click OK to continue.
Expanding RAID array
Reconfigure or migrate a virtual disk (VDs) to increase the capacity or change the RAID level of the virtual disk. For more information
about reconfiguration of virtual disks, see Starting and target RAID levels for virtual disk reconfiguration and capacity expansion, and
Reconfiguring or migrating virtual disks.
LTO-4 Tape drives are not supported on PERC
Tape drives are not supported on PERC. Use a 6Gbps SAS HBA or an equivalent SAS HBA that is not designed with RAID.
Limitations of HDD size on H310
The PowerEdge RAID Controller H310 does not support HDD size more than 2 TB. HDD size has this limitation.
System logs show failure entry for a storage controller
even though it is working correctly
The PowerEdge RAID Controller (PERC) family of enterprise-class controllers is designed for enhanced performance, increased reliability,
fault tolerance, and simplified management. These controllers provide a powerful, easy-to-manage way to create a robust infrastructure
and help maximize server uptime. The battery installed on these controllers help in ensuring data integrity in case of power outages.
About this task
When the controller battery is discharged, the system recharges the battery and reconditions it. During this reconditioning, you may see a
failure in the system logs. To confirm that the battery is working correctly, check the hardware details on any of the Dell EMC systems
management solutions. This error can also be resolved by clearing the static build-up in the system. To clear the static build-up, perform
the following steps:
Troubleshooting hardware issues
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