Using High Availability Monitors (June 2007)

Monitoring Database Resources
Rules for Using the HA Database Monitor with ServiceGuard
Chapter 370
Rules for Using the HA Database Monitor with
ServiceGuard
The HA Database Monitor with ServiceGuard provides package failover
if database servers fail or if the usage or number of connections exceeds
specified levels. For example:
• In a cluster where a database is accessed by multiple database
servers on the same host, you may want to fail a package over if the
database servers on that host are stopped for some reason, such as
shutting down the instance or if one or more of the server processes
aborts.
• In a cluster where database access is limited by a maximum number
of connections, you may want to fail a package over when this
maximum number is reached, to a host where there is no limit set.
• In a cluster where the host cache is not being effectively utilized, you
may want to fail a package over to a host that is less busy.
Database availability is based on database status and database server
status. See the manual Using the Event Monitoring Service
(B7609-90021) for information on configuring package dependencies.
In addition to configuring databases as ServiceGuard package
dependencies, you may also want to send notifications about events to a
system management tool such as HP Open View IT/Operations or
Network Node Manager. Although ServiceGuard and EMS work together
to provide package failover, they do not send events or log the source of
the failure. Also, failures may not cause a package failover, but may
expose a single point of failure that you wish to know about. Therefore,
it is recommended that you also configure resource monitoring requests
from the HP SMH interface.
NOTE The following sections provide an example of the parameters and
settings for the vendor database software from Oracle Corporation.
Currently this is the only vendor database that can be configured as a
ServiceGuard package dependency.