VCEM Profile Failover and Profile Moves

Actions performed by the Failover Job
The Failover Job performs the following actions. In the text below, “Exit on error” means that
if the corresponding step does not complete successfully, the failover job will stop processing
and exit.
• Locks the VC Domain Group of the source server to other operations in VCEM for the
remainder of the job to avoid possible conflicting actions by other users or processes.
• Checks that the source server is a ProLiant server blade. Exit on error.
• Powers off the source server using “press and hold” (hard power off).
• Picks a qualified spare server from the source server’s VC Domain Group. The spare is the
first one found that meets all the following criteria. If no spare server is found, then exit on
error:
• The spare bay has no profile.
• The spare bay server is physically present.
• The model of the spare server is the same as the source server’s [note: the server model
generation is not differentiated; that is, a BL465-c G1 and a BL465-c G5 pass as the
same model.
• The spare server is powered off.
• Moves the profile from the source to the spare bay. Exit on error. As part of this operation:
• Removes the source server’s host name and IP address information in HP SIM.
• Removes the spare designation from the spare bay.
• Powers on the spare server, thereby booting the SAN-attached system drive image. As
part of this operation:
• Schedules HP SIM discovery to be run on the spare server in 10 minutes hence. This
will associate with HP SIM the host name and IP addresses of the spare server. To be
effective, the operating system booted on the spare server must have established its
network communications by the time HP SIM discovery runs.
• The job completes by unlocking the resources of the VC Domain Group.
Capabilities and limitations of Profile Failover
An understanding of the capabilities and limitations of Profile Failover is helpful to make the
best use of this feature.
When Profile Failover is complete, the workload of the source (production) server has been
restarted on a different (spare) server blade and the memory resident software and data
have been refreshed from disk. This means:
• Problems due to server hardware malfunction are fixed by replacing server hardware.
•
Problems due to aberrant software or data states that can be rectified by refreshing
software and data from disk are fixed.
• User sessions established at the time of the failover might be interrupted.
• In HP SIM, 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:
• Loss of connectivity with dependent resources residing on an attached SAN or Ethernet.
• Data or software corruption or related loss of state integrity.