Cost-Effective High-Availability Solutions with HP Instant Capacity on HP-UX

Figure 5: TiCAP example after failure and one day after activations on Sys2
When the failure on Sys1 is resolved, you can stop the use of TiCAP on Sys2 by deactivating the six
processor cores:
Sys2> icapmodify -d 6
You can also redeploy the applications to Sys1.
HP Serviceguard considerations
The TiCAP solution can be automated using the Serviceguard product. The basic steps include:
• Configuring a Serviceguard cluster with packages set up to automatically fail over to the standby
server (adoptive node).
• Purchasing and applying TiCAP to the standby server.
The amount of TiCAP to purchase depends on:
– The number of additional processor cores that need to be activated on the standby server to run
the package
– The amount of time needed to cover downtime
• Creating scripts that provide customized processing on the start-up and shutdown of the package to
activate and deactivate the use of TiCAP, as necessary. In this scenario, failback (either automatic
or manual) is essential to avoid continuous consumption of TiCAP.
• Preparing for the next potential failure. After a successful failover and subsequent failback to the
primary server or servers, additional TiCAP should be purchased and applied to the standby servers
in preparation for potential failures.
The application start-up time is slightly longer when compared to use of a typical Serviceguard
package control script that does not invoke TiCAP commands because of the overhead in sensing the
status of the active system and activating the inactive cores on the failover or failback system.
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