Service Considerations For The Cache Battery Pack - IBM 8412-EAD Manual

Review the SAS subsystem configuration that uses a two-way split backplane example. This configuration
consists of two independent embedded SAS adapters, each controlling three of the six disk bays. In the
following figure, the highlighted disk bays represent the disk bays that are controlled by each embedded
storage adapter (D1- D3 and D4 - D6).
Review the SAS subsystem configuration that uses a dual storage IOA with internal drives example. If
you add the optional 175 MB Cache Raid – Dual IOA enablement card (FC 5662), it creates a
configuration consisting of two embedded SAS adapters in a dual storage IOA or high availability (HA)
RAID mode. Both adapters mutually control all of the six disk drive bays and have access to common
data (see the following figure). In addition, the two rechargeable battery packs on this feature enable
nonvolatile write cache of the embedded SAS storage adapters.
Attention: You must do proper planning and follow proper procedures before adding or removing the
175 MB Cache Raid – Dual IOA enablement card (FC 5662) to maintain system availability and to prevent
possible data loss.
Related information:
Removing the 175 MB Cache RAID – Dual IOA enablement card from the 8412-EAD, 9117-MMB,
9117-MMC, 9117-MMD, 9179-MHB, 9179-MHC, or 9179-MHD
Installing the 175 MB Cache RAID – Dual IOA enablement card in the 8412-EAD, 9117-MMB,
9117-MMC, 9117-MMD, 9179-MHB, 9179-MHC, or 9179-MHD
Important partitioning considerations with dual-slot and multi-adapter configurations

Service considerations for the cache battery pack

To prevent data loss, follow proper procedures before replacing the cache battery pack on the 175 MB
cache RAID – dual IOA enablement card.