Installation guide

Note
Use a descriptive name that clearly distinguishes the service from other services in the
cluster.
Figure 5.12. Adding a Cluster Service
4. If you want to restrict the members on which this cluster service is able to run, choose a failover
domain from the Failover Domain drop-down box. (Refer to Section 5.6, “Configuring a Failover
Domain” for instructions on how to configure a failover domain.)
5. Autostart This Service checkbox — This is checked by default. If Autostart This Service is
checked, the service is started automatically when a cluster is started and running. If Autostart
This Service is not checked, the service must be started manually any time the cluster comes up
from stopped state.
6. Run Exclusive checkbox — This sets a policy wherein the service only runs on nodes that have
no other services running on them. For example, for a very busy web server that is clustered for
high availability, it would would be advisable to keep that service on a node alone with no other
services competing for his resources — that is, Run Exclusive checked. On the other hand,
services that consume few resources (like NFS and Samba), can run together on the same node
without little concern over contention for resources. For those types of services you can leave the
Run Exclusive unchecked.
Note
Circumstances that require enabling Run Exclusive are rare. Enabling Run Exclusive
can render a service offline if the node it is running on fails and no other nodes are empty.
Red Hat Enterprise Linux 4 Cluster Administration
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