Installation guide

title Red Hat Enterprise Linux Server (2.6.18-36.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-36.el5 ro root=/dev/VolGroup00/LogVol00
console=ttyS0,115200n8 acpi=off
initrd /initrd-2.6.18-36.el5.img
In this example, acpi=off has been appended to the kernel boot command line — the line
starting with "kernel /vmlinuz-2.6.18-36.el5".
Example 2.11. Kernel Boot Command Line with acpi=off Appended to It
4. Considerations for Configuring HA Services
A cluster service is a group of cluster resources configured into a coherent entity that provides
specialized services to clients. A cluster service is represented as a resource tree in the cluster
configuration file, /etc/cluster/cluster.conf (in each cluster node). In the cluster
configuration file, each resource tree is an XML representation that specifies each resource, its
attributes, and its relationship among other resources in the resource tree (parent, child, and
sibling relationships).
Note
Because a service consists of resources organized into a hierarchical tree, a
service is sometimes referred to as a resource tree or resource group. Both
phrases are synonymous with cluster service.
At the root of each resource tree is a special type of resource — a service resource. Other types
of resources comprise the rest of a service, determining its characteristics. Configuring a cluster
service consists of creating a service resource, creating subordinate cluster resources, and
organizing them into a coherent entity that conforms to hierarchical restrictions of the service.
There are two major considerations to take into account when configuring a cluster service:
• The types of resources needed to create a service
• Parent, child, and sibling relationships among resources
The types of resources and the hierarchy of resources depend on the type of service you are
configuring.
The types of cluster resources are listed in Appendix C, HA Resource Parameters. Information
about parent, child, and sibling relationships among resources is described in Appendix D, HA
Chapter 2. Before Configuring a Red Hat Cluster
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