Cisco UCS C220 M3, Инструкция по установке и обслуживанию

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C-4
Cisco UCS C220 Server Installation and Service Guide
OL-25760-01
Appendix C RAID Controller Considerations
Mixing Drive Types in RAID Groups
Mixing Drive Types in RAID Groups
Table C-3 lists the technical capabilities for mixing hard disk drive (HDD) and solid state drive (SSD)
types in a RAID group. However, see the best practices recommendations that follow for the best
performance.
Table C-3 Drive Type Mixing in RAID Groups
Mix of Drive Types
in RAID Group Allowed?
SAS HDD + SATA HDD Yes
SAS SSD + SATA SSD Yes
HDD + SSD No
Best Practices For Mixing Drive Types in RAID Groups
For the best performance, follow these guidelines:
• Use either all SAS or all SATA drives in a RAID group.
•
Use the same capacity for each drive in the RAID group.
•
Never mix HDDs and SSDs in the same RAID group.
RAID Backup Units
This server supports installation of one SuperCap Power Module (SCPM). The unit mounts to a holder
on the left-side air baffle (see
Figure 3-24 ).
Note
The iBBU09 battery backup unit (BBU) has been phased out by Cisco and replaced with the SuperCap
power module (SCPM). If you are replacing a BBU, order the SCPM for the replacement
(UCS-RAID-CV-SC=). Cards that used the BBU are compatible with the SCPM.
• The optional SCPM provides approximately 3 years of backup for the disk write-back cache DRAM
in the case of sudden power loss by offloading the cache to the NAND flash.