Filter
Top Products
Recovering cache data
If a system power loss or improper system shutdown has occurred:
1. Ensure all online physical disks are still connected.
2. Restore the system power.
3. Boot the system.
Virtual disks are automatically imported and preserved cache (if any) will be flushed to the physical
disks of appropriate virtual disks. If preserved cache is still present, there could be situations
preventing the flushing of preserved cache data.
NOTE: For more information on recovering the cache data, see the Dell Chassis Management
Controller for Dell PowerEdge VRTX User’s Guide at dell.com/poweredgemanuals.
NOTE: If there is preserved cache in Shared PERC 8, you can clear the preserved cache in the
CMC. If there is no preserved cache, this option is not displayed in CMC which indicates that
the preserved cache data is recovered and written to the physical disks successfully.
NOTE: If preserved cache is discarded, preserved cache data is not written to the physical disks.
Ensure that the preserved cache data is not critical before discarding.
Battery Transparent Learn Cycle
A transparent learn cycle is a periodic operation that calculates the charge that is remaining in the battery
to ensure there is sufficient energy. The operation runs automatically, and causes no impact to the
system or Shared PERC 8 card performance. The Shared PERC 8 card automatically performs the
Transparent Learn Cycle (TLC) on the battery to calibrate and gauge its charge capacity once every 90
days.
NOTE: Virtual disks stay in Write-Back mode, if enabled, during transparent learn cycle. If the TLC
completes, the Shared PERC 8 card sets the next TLC to +90 days.
TLC Time Frame
The time frame for completion of a learn cycle is a function of the battery charge capacity and the
discharge and charge currents used. For Shared PERC 8 card, the expected time frame for completion of
a learn cycle is approximately seven hours.
Conditions For Replacing The Battery
The Shared PERC 8 battery is marked Failed in the Battery Status in the CMC, when the state or health of
the battery is declared bad. If battery is declared failed, then the firmware runs learn cycles in subsequent
reboots until the battery is replaced. After the battery is replaced, the virtual disk then transitions to Write-
Back mode.
The Controller Failover Feature
The dual-controller configuration of the VRTX system has two shared-PERC controllers configured in an
active-passive mode. A single active controller monitors all the storage related processes. When the
active controller stops functioning, the passive controller acts as a peer hot-spare, and takes over the
functions of the active controller in a seamless manner. Although the transition is seamless with respect
to the operating system, there may be some temporary performance impact in the course of the failover.
20