Installation guide

Note

You must specify both parameters together; the use of either parameter by itself is undefined.

3.3. Resource T rees - Basics / Definit ions

The following illustrates the structure of a resource tree, with a correpsonding list that defines each

area.

</fs>

</service>

Resource trees are XML representations of resources, their attributes, parent/child and sibling

relationships. The root of a resource tree is almost always a special type of resource called a

service. Resource tree, resource group, and service are usually used interchangeably on this wiki.

From rgmanager's perspective, a resource tree is an atomic unit. All components of a resource

tree are started on the same cluster node.

fs:myfs and ip:10.1.1.2 are siblings

fs:myfs is the parent of script:script_child

script:script_child is the child of fs:myfs

3.3.1. Parent / Child Relat ionships, Dependencies, and St art Ordering

The rules for parent/child relationships in the resource tree are fairly simple:

Parents are started before children

Children must all stop (cleanly) before a parent may be stopped

From these two, you could say that a child resource is dependent on its parent resource

In order for a resource to be considered in good health, all of its dependent children must also be

in good health

3.4 . Service Operat ions and St at es

The following operations apply to both services and virtual machines, except for the migrate

operation, which only works with virtual machines.

3.4 .1. Service Operat ions

The service operations are available commands a user may call to apply one of five available

actions, defined in the following list.

enable — start the service, optionally on a preferred target and optionally according to failover

domain rules. In absence of either, the local host where clusvcadm is run will start the service. If

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