Cisco UCS C220 M3, Инструкция по установке и обслуживанию

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Cisco UCS C220 Server Installation and Service Guide
OL-25760-01
Chapter 3 Maintaining the Server
Installing or Replacing Server Components
•
Performance Mode–Prioritizes performance memory operation. If you mix low-voltage DIMMs with
standard DIMMs, the system defaults to this setting.
Step 5
Press F10 to save your changes and exit the setup utility.
Memory Mirroring
When memory mirroring is enabled, the memory subsystem simultaneously writes identical data to two
channels. If a memory read from one of the channels returns incorrect data due to an uncorrectable
memory error, the system automatically retrieves the data from the other channel. A transient or soft error
in one channel does not affect the mirrored data, and operation continues unless there is a simultaneous
error in exactly the same location on a DIMM and its mirrored DIMM. Memory mirroring reduces the
amount of memory available to the operating system by 50% because only one of the two populated
channels provides data.
Note
You must choose to enable memory mirroring in the server BIOS setup utility, under
Advanced > Memory Configuration > Mirroring.
If you choose to enable memory mirroring, populate the DIMM slots in the order shown in Table 3-5 .
Table 3-5 Memory Mirroring DIMM Population
Number of DIMMs
per CPU CPU 1 Population CPU2 Population
4 A1, B1; A2, B2 E1, F1; E2, F2
6 A1, B1; C1, D1; A2; B2 E1, F1; G1, H1; E2, F2
8 A1, B1; C1, D1; A2, B2; C2, D2 E1, F1; G1, H1; E2, F2; G2, H2
DIMM Replacement Procedure
This section includes the following topics:
•
Identifying a Faulty DIMM, page 3-21
•
Replacing DIMMs, page 3-21
Identifying a Faulty DIMM
Each DIMM slot has a corresponding DIMM fault LED. See Figure 3-3 for the locations of these LEDs.
The LEDs light amber to indicate a faulty DIMM. Power must be present in the server for these LEDs to
operate.
Replacing DIMMs
To install a DIMM assembly, follow these steps:
Step 1
Remove the DIMM that you are replacing:
a.
Power off the server as described in the “Shutting Down and Powering Off the Server” section on
page 3-7 .