The Raid Cache Module And Supercapacitor; Hpe Sas Expander Card (Hpe Storeonce 5100 System And Hpe Storeonce 3500 Series) - HP StoreOnce 3100 Maintenance And Service Manual

The RAID cache module and SuperCapacitor

There is one SuperCapacitor and cache module for each RAID Controller. The RAID cache module is slotted
onto the RAID card; the SuperCapacitor is located in the center of the unit, clipped to the floor of the chassis
behind the disk cage.
These items ensure that cache contents are maintained after a loss of power. The LEDs on the cache module
flash when the SuperCapacitor is disconnected and POST error messages provide more information.
NOTE:
The recommendation is to replace both the SuperCapacitor and RAID cache module at the same time,
regardless of which element has failed.
NOTE:
Never move cache modules from one RAID controller to another within or between systems.
If the SuperCapacitor is disconnected on the RAID card in the HPE StoreOnce System, the system will not
boot. If boot fails, it is a good idea to check that the SuperCapacitor is seated correctly.
If the SuperCapacitor or cache module has failed, the system may still boot with error messages and it will run
more slowly. Remove and dispose of the old module, and replace it with the new one. Check that the cable is
connected correctly to the SuperCapacitor.
Figure 22: SuperCapacitor module connector on RAID card
1
SuperCapacitor connector
HPE SAS expander card (HPE StoreOnce 5100 System and HPE StoreOnce
3500 Series)
If no disks are showing on the Storage-Shelves page of the StoreOnce GUI, there may be a problem with the
HPE SAS expander card.
The part number for a replacement card is: 761879-001. It must be installed in PCIe slot 2.
Mini-SAS cables connect the RAID controller card to the SAS expander card, and the SAS expander card to
the hard disk drive backplane.
1 2
2
LEDs
The RAID cache module and SuperCapacitor 55