Planning for service processor failover

The 570 models support redundant service processor configurations that allow you to plan for dynamic failover. It is important to understand the considerations and requirements for a redundant service processor configuration to prepare for enabling the failover capability.

The redundant service processor capability enables you to configure a secondary service processor that is activated when the primary service processor fails. This information describes the considerations and requirements for enabling this capability, whether you are installing a new system with redundant service processor capability or upgrading an existing system.

Preparing your network environment for failover
_	Network requirements Service processor failover is supported in a private or open service network, using static or dynamic IP addressing.
_	HMC setup requirements You must have a Hardware Management Console (HMC) to enable the redundant service processor capability. The HMC is required to be at the same level or a higher level as the system firmware for service processor failover capability. Currently, two HMC configurations are supported for redundant service processor enablement, as shown in the following diagrams. Using a single Hardware Management Console configuration Using a redundant Hardware Management Console configuration
_	Cabling requirements If you are upgrading a system with a single service processor to a redundant service processor system, plan for any additional cables that you will need for this environment: You must have enough Ethernet cables to connect both service processors to the hub. You must provide your own hub. You must have a cable to connect between the two service processors on the HMC2 port on a Power5 system. If you have I/O towers or I/O drawers in your configuration, you will need additional System Power Control Network (SPCN) cables to connect the two service processors together and to connect the service processors to the I/O tower or I/O drawer. For more information about cabling for a redundant service processor, see Replace the model 570 or 9116-561 service processor cable
Preparation checklist
Use this checklist to prepare for redundant service processor enablement.
_	Review the configuration requirements discussed in the preceding section.
_	Decide which HMC configuration you will use (single HMC configuration or redundant HMC configuration).
_	Determine if additional cables are required for the redundant service processor.
_	If you are replacing your service processor to upgrade to a redundant service processor, ensure that you first back up your logical partition (LPAR) profiles and your service processor settings. Replacing your service processor causes a loss of LPAR configurations. Back up your partition profile data to a named file, using the instructions described in Backing up partition profile data. Make sure you specify a backup file name and do not use the HMC default file name. This enables you to preserve a perpetual copy of the backup settings on the HMC. Record the backup file name that you specify because you will use this file name to restore your partition data. See Restoring Profile Data.
_	Ensure that your system meets the supported hardware and software version requirements for the service processor failover functionality. See the IBM® Prerequisite Web site at http://www-912.ibm.com/e_dir/eServerPrereq.nsf for information.
_	Ensure that the service processors in the top two drawers have the same firmware level.

Enabling service processor failover

After the redundant service processor environment setup has been completed, you can enable the service processor failover from the HMC. See Enabling service processor failover to enable the redundant service processor for failover mode.

Note: To initialize service processor failover, the first time you enable it your system must be in the powered-off state. For information about powering off and powering on your managed system from the HMC, see Powering on and off a managed system. After the initial enablement on the Power5 system, powering off the system is not required to enable or disable the failover.