Implement high-availability solutions with HP Instant Capacity - easily and effectively

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• Maximum core usage rights are seized—All the usage rights except one will be seized from the server.
• Expiration of seized usage rights (complete server failure)—If at the time of an attempted rights seizure the OA
module or the server complex are unreachable, the rights seizure is instead treated as a loan of usage rights from the
specified member to the group. The loan expires 30 days from the first use of the icapmanage -x command. If none of
the member partitions are reachable by the expiration date for a particular member, the usage rights are
automatically restored (or reassigned) to the member from which they were seized. If, however, one of those
members reconnects to the group before the expiration, the loan can be committed, with the usage rights actually
transferred from the member.
In the event a system cannot reconnect to the Group Manager within the 30-day period, (for example, due to a natural
disaster such as an earthquake) you can extend the expiration of the seized usage rights. This extension is applied to the
Group Manager through a codeword obtained from HP support.
• Core usage rights are seized from the complete complex.
• You can seize usage rights from a complex only when the OA is down.
• An OA must be unavailable for usage rights to be seized—usage rights can only be seized if the OA is unavailable as
determined by the ping command. If a Serviceguard package needs to fail over for other reasons, then the script must
account for those possibilities. For example, if remote operations can still be performed on the active node, the script
can acquire usage rights directly by deactivating cores on the active complex.
• You cannot run a Group Manager in a virtual machine.
• The active Group Manager must have network connectivity.
Scripts for implementing failover with HP Serviceguard
While you can implement rights seizure as part of an automatic failover system, you must ensure resources are seized
appropriately and in a manner that will not cause problems when the failures are corrected. The iCAP software
determines that a partition is down based on whether the ping command is unsuccessful for the partition. However, ping
can be unsuccessful even though the system is functional (for example, if a network connection is interrupted). In this
case, rights seizure might be inappropriate, leaving workloads without the necessary resources.
Note: These scripts are for illustrative purposes. They provide a starting point for implementation and assume that all application workloads are under the
control of Serviceguard. The sample scripts should be modified to fit your specific requirements. In particular, the startup script uses remsh for a remote
operation, but a more secure implementation would use secure shell (ssh). Also, the script should be made more robust by checking for errors and other
possible cluster states, and exiting with appropriate return status values. The scripts are for customer-defined run/halt commands used in the
Serviceguard legacy package format; however, they can easily be modified to use external_scripts with the Serviceguard modular package format. These
sample scripts are not part of either the iCAP or Serviceguard products and are not supported by HP.