IBM ServeRAID, User Reference

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v The stripe-unit size and level of BIOS and firmware code must be the same on
both controllers.
v All physical drives must be configured in arrays. A failover pair must not contain
any physical drives in the ready state.
v You must set the write-cache mode of all logical drives on the active controller to
write through.
Note: If your ServeRAID controller has a battery-backup cache, it is disabled
when you create a failover pair. The write-cache mode is automatically
changed from write back to write through.
v All logical drives must have unique shared merge-group numbers.
v When you use multiple failover pairs in a system, each set of controllers must
have unique controller and partner names.
v All on-board ServeRAID controllers must be enabled, even if the controller is not
used.
The following restrictions apply:
v
Hot-spare drives are not supported in a failover environment. The exception is
the built-in hot-spare that is part of a RAID level-5E logical drive.
v You cannot hot add a controller and then configure it as part of a failover pair.
v
A failover pair and a ServeRAID adapter defined as a Microsoft Cluster Server
(MSCS) resource cannot coexist in the same server.
v A logical drive cannot failover if it is any of the following:
– A RAID level-5 or level-5E logical drive in a critical state
– A RAID level-5 or level-5E logical drive that is undergoing a rebuild operation
– A RAID level-5E logical drive that is undergoing a compression or
decompression operation
– A logical drive undergoing a logical-drive migration
Preparing the active controller
This section covers the following steps:
Step 1. Installing the ServeRAID controller that you will designate as the active
controller.
Step 2. Configuring the active controller for failover.
Step 3. Connecting the active controller to the enclosure; then, starting the server
with the IBM ServeRAID Support CD in the CD-ROM drive.
Step 4. Configuring arrays and logical drives.
Step 5. Installing the appropriate device driver.
Installing the active controller
If you have not yet installed the ServeRAID controller that you will designate as the
active controller, do so now. For instructions, see the
IBM Installation Guide that
came with the controller.
Important
Do not install the controller you will designate as the passive controller until instructed to do
so.
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IBM ServeRAID: User’s Reference, Version 5.10