VCEM Profile Failover and Profile Moves White Paper

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• Aberrant software or data states which can be corrected by refreshing software and data
from disk.
Ensure that you are aware of the following points during failover:
• User sessions established at the time of the failover might be interrupted.
• In HP Systems Insight Manager, hostname, and IP address associations are removed from
the source server and reestablished with the spare about ten minutes after failover
completes.
• Problems that profile failover does not address include:
o Loss of connectivity with dependent resources residing on an attached SAN or
Ethernet.
o Data or software corruption or related loss of state integrity.
o Operating errors and system configuration errors.
Profile failover depends on the following:
• Servers must be pre-configured to boot from SAN on power-up.
• Servers must have no dependency on a local drive.
• The source server’s system drive image must be able to run on the hardware and firmware
configuration of any spare server in the VC Domain Group that is the same model as the
source server. This includes server models of different generations, for example, the BL465-
c G1 and BL465-c G5.
Recommendations and best practices
It is possible that a small difference in the hardware or firmware configuration of two
different servers can create an incompatibility, such that a system drive image that works on
one server does not work on the other, or performs at a degraded level. Therefore to ensure
the best failover results:
• Standardize on one hardware configuration for all servers of the same model for each VC
Domain Group. For each model, implement procedures to keep all firmware at the same
revision levels across the server population. It is best to upgrade the OA, iLO, and server
firmware to the latest revisions.
• Avoid placing different generations of the same model server in the same VC Domain
Group. The internal composition of the hardware and firmware items across different
generations of the same model is often significantly different.
• Test to ensure boot images reliably start and run on all the server configurations that could
possibly be used, especially if you need to use different hardware and firmware
configurations for the same server model within a VC Domain Group.
Take a step-by-step approach to direct initiation of failover using HP Systems Insight
Manager Automatic Event Handling. If you choose to implement event-initiated failover, be
certain that your selected collection of failover events has a level of problem detection
accuracy that is consistent with your operating procedures and service level objectives. For
more information see
Initiating Failover using HP Systems Insight Manager Automatic Event
Handling.