HP Instant Capacity Version 10.x User Guide (5900-1581, March 2011)

The Instant Capacity software determines that the partition is down based on whether the ping
command is unsuccessful for the partition. In some circumstances, ping might be unsuccessful but
the system remains functional (for example, if a network connection is interrupted). In this case,
rights seizure may be inappropriate and leave workloads without the necessary resources.
There are no restrictions regarding the type of environment from which rights were seized. Rights
that are seized from either an nPartition environment or a virtual partition environment can be
deployed on any member of the GiCAP group, regardless of the target environment type.
Additional HA Solutions
Although rights seizure is the main method used in a GiCAP high availability (HA) scenario, there
are additional methods and configurations allowing GiCAP to provide you with HA solutions:
• You can use GiCAP to move capacity from one or more nonproduction servers, such as test
servers, during a failover situation. You have a set of standby servers that are part of a group
and can pool their resources to provide failover capability.
• You can combine GiCAP with temporary capacity. If you have a set of nonproduction servers,
and some of those servers contain temporary capacity, temporary capacity from the entire
group is made available during a failover situation. Temporary capacity is not seizable, so
any HA solution involving temporary capacity must ensure that it is available on the standby
server.
• Systems with full usage rights can also be a part of a GiCAP group and can be used as donor
systems, contributing usage rights to the group and allowing additional activations on member
systems with Instant Capacity components.
Summary of Rights Seizure
The following summarizes usage rights seizure on GiCAP systems:
• iCAP can seize usage rights from an unavailable server.
Usage rights can be seized from a group member even if the entire server is unavailable. In
this case, usage rights expire after 10 days and revert to the original partition.
• Only core usage rights can be seized.
While GiCAP allows migration of all types usage rights between member servers (cores, cells,
and memory), seizure from a failed partition is only for core usage rights. If cell or memory
usage rights are needed, partitioning tools such as the parmodify command can be used
either remotely or on an accessible partition to remove one or more cells from the unavailable
partition, making usage rights available. Changing the use-on-next-boot (UONB) flag to false
for an inactive cell also releases the cell usage right and associated memory usage rights.
• Maximum core usage rights are seized.
There is no way to specify the number of core usage rights that are seized. Instant Capacity
seizes the maximum number possible, while ensuring that the nPartition can still be booted.
This seizure results in a partition with one core usage right for each active cell upon reboot
of the server.
• Expiration of seized usage rights (complete server failure)
If at the time of an attempted rights seizure all member partitions are unreachable, the right
seizure is instead treated as a loan of usage rights from the specified member to the group.
The loan expires 10 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 member partitions reconnects to the group before the expiration,
the loan can be committed, with the usage rights actually transferred from the member.
86 Global Instant Capacity