IBM ServeRAID, User Reference

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Important
The following procedure requires specific configuration settings for the ServeRAID
controller. If the server and controller that are being replaced are functional, you can obtain
these settings from the controller. However, if the controller or the server is not functional,
you will need a record of the settings, such as one created when the controller was
previously configured. If you are replacing your ServeRAID controller at the same time as
your server, you
must have correct configuration information to complete this procedure.
Complete the following steps to recover from a failed server:
1. Shut down the failed server.
2. Remove all local physical drives from the failed server.
As you remove your physical drives, be sure to note the bay in which each drive
was installed. If you are replacing your failed server with an identical server, you
can reinstall the drives in an identical configuration and get your server up and
running quickly.
3. If the ServeRAID controller is functional, remove it from the failed server. As you
remove the controller from the failed server, be sure to note the following:
v Which SCSI cables are connected to the SCSI channel connectors on the
controller
v Which PCI slot has the controller installed
4. Install all the local physical drives into the new server, using the location
information you recorded in step 2.
For information on how to install a physical drive, see the documentation that
comes with your server. If you are replacing the failed server with an identical
server, install each physical drive in the same bay as the one it was removed
from in the failed server.
5. If the ServeRAID controller in the failed server is not functional , or if you are not
sure, continue with “Recovering from a failed ServeRAID controller”. Otherwise,
perform the following steps with the functional ServeRAID controller:
a. Install the controller in the new server.
b. Reinstall the cables as they were in the failed server.
c. Start the server.
Recovering from a failed ServeRAID controller
You must have the following configuration information to configure your new
ServeRAID controller:
v SCSI initiator IDs
The SCSI initiator IDs for a non-shared SCSI channel are set to 7. For shared
SCSI channels, the SCSI initiator IDs must be 7 or 6; they must be different from
the SCSI initiator IDs for the corresponding SCSI channels of the cluster partner
controller. Therefore, if you can obtain the SCSI initiator IDs for the
corresponding cluster partner system, you know the correct SCSI initiator IDs for
this system. For example, if the cluster partner system-shared SCSI initiator IDs
were set to 7, the controller you are replacing would need to have its SCSI
initiator IDs set to 6 for the shared channels.
v Controller and partner name
You can also determine the names for the controller being replaced by reading
the settings from the cluster partner system.
v Stripe-unit size
The stripe-unit size must be the same on both controllers in a high-availability
cluster.
Chapter 18. Solving ServeRAID problems
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