Installation guide

7.4 Cluster Resources and Services
There are many types of cluster resources that can be configured. Resources are bundled
together to highly available services; i.e., a service consists of one or more cluster resources.
Resources can be used by any cluster service that requires one. Once associated with a
cluster service, it can be relocated by a cluster member if it deems it necessary, or manually
through a GUI interface, a web interface (conga) or via command line. If any cluster member
providing the service becomes unable to do so (e.g., due to hardware or software failure,
network/connectivity loss, etc.), the service with all its resources will automatically migrate to
an eligible member.
Reference the Adding a Cluster Service to the Cluster section of Configuring and Managing a
Red Hat Cluster for more information.
Highly available cluster services are configured within the <service> tag. Consider defining
the following attributes:
Attribute Description Required
name The name of the service or resource group Yes
domain The failover domain associated with this
service
No
autostart If set to yes, the service will automatically be
started after the cluster forms a quorum. If set
to no, this resource group will start in the
'disabled' state after the cluster forms
a quorum. Default is 1.
No
exclusive If set, this resource group will only relocate to
nodes which have no other resource groups
running in the event of a failure.
No
recovery This currently has three possible options:
"restart" tries to restart failed parts of this
resource group locally before attempting to
relocate (default); "relocate" does not bother
trying to restart the service locally; "disable"
disables the resource group if any component
fails. Note that any resource with a valid
"recover" operation that can be recovered
without a restart will be.
No
The following resource types will be defined to provide the high availability functionality for
SAP.
42 | www.redhat.com