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

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Monitor Group Manager health
Starting with iCAP version 10.05 or later, you can now intelligently monitor the health of a group manager using
Serviceguard scripts. Based on the health of the GM you can further decide if you want to failover to the Standby
Group Manager.
The main purpose of the Serviceguard cluster containing the Group Manager is that the Group Manager is available at all
times to manage the group. However, if the partition remains active Serviceguard does not monitor the Group Manager.
So, we must write scripts to check the status of the Group Manager and based on output of these scripts we decide to
failover the Group Manager. You can find sample scripts and directions to monitor the health of the Group Manager in
the “Scripts for Monitoring the Health of the Group Manager” subsection.
Additional HP GiCAP high-availability solutions
In the previous examples, we saw that GiCAP enables you to move capacity from one server partition to
another server. However, there are additional ways and configurations that enable you to use GiCAP to provide
high-availability solutions:
• You can use GiCAP to move processor cores 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 TiCAP in a similar scenario. If you have a set of nonproduction servers, and some of those
servers are provisioned with TiCAP (perhaps for use during peak production times), then all TiCAP from the entire
group is available during a failover situation. However, because the TiCAP is available to all group members, it may be
inadvertently consumed such that an insufficient balance is actually available in a failover situation. Take care to
ensure enough TiCAP is available if you are relying on it to provide failover.
• Systems with full usage rights can also be 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 iCAP components.
• Rights that are seized from one server can be deployed on any member of the GiCAP group, regardless of the target
environment type.
Summary
You can use HP iCAP in combination with HP Serviceguard to reduce the cost of implementing high-availability solutions
for mission-critical environments. The rich functionality of both products provides a wide spectrum of
possible solutions:
• For many Serviceguard configurations, the purchase and installation of iCAP processors provides—at a much reduced
price—standby processing capacity for certain specific hardware failures. It also provides the foundation for more
sophisticated high-availability solutions.
• When dynamically resizable partition configurations are used, the purchase and installation of iCAP components
(cores and blades with memory) enables standby partitions to be provisioned cost-effectively and to share resources
under some situations. Redundancy of components can be provided without doubling the price.
• Adding TiCAP to a system with iCAP components provides additional flexibility and standby capacity. This part of the
solution is not limited to a particular configuration but provides extra standby capacity only for processor cores. It is
used in situations in which you can easily predict the duration of the failure, because it requires incremental purchases
of TiCAP. The requirement to do failback is compelling for the same reason.
• GiCAP extends these capabilities by enabling multiple servers of a group to share resources (usage rights and TiCAP).
Sharing these resources can be beneficial in either load balancing or failover solutions.
• GiCAP in combination with TiCAP provides the most cost-effective and flexible solution and can potentially be used in
all high-availability configurations.
• In most cases, you can easily and automatically add processing power in an iCAP high-availability solution, so that the
failover solution actually has more resources available than during normal processing, if necessary.
• HP Serviceguard can be used in combination with many iCAP solutions to provide a more automated and
comprehensive solution.