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Cisco UCS C220 M4 Server Installation and Service Guide
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Appendix C RAID Controller Considerations
Supported RAID Controllers and Required Cables
Write-Cache Policy for Cisco 12G SAS Modular RAID Controller
For this server and other Cisco Generation M4 servers, the default write-cache policy for the Cisco Modular
RAID controller is
Write Through
(irrespective of the presence of a charged Supercap power module or
“good BBU”). This utilizes the optimal performance characteristics of the controller.
If you have Cisco IMC 2.0(5) or later firmware installed to the M4 server, the write policy can be set to
Write
Back
, if preferred.
You can set the write policy using the following methods:
•
For standalone servers, use the Cisco IMC interface to set Virtual Drive Properties > Write Policy. See
the “Managing Storage Adapters” section in your Cisco IMC Configuration Guide.
Cisco IMC GUI and CLI Configuration Guides
•
For Cisco UCS-integrated servers, use the Cisco UCS Manager interface to set the write-cache policy
as part of virtual drive configuration in your storage profile.
Cisco UCS Manager Configuration Guides
•
Use the LSI Option ROM Configuration Utility.