Guidelines for Creating an IP Dependancy

How and/or when you are going to create a parent/child dependency between a LifeKeeper-protected application and a LifeKeeper-protected IP address is typically dependent on the LifeKeeper-protected application. For example, in a LifeKeeper-protected Apache environment, the parent/child dependency is created during the creation of the Apache resource hierarchy (assuming you have already created a protected IP address). In other applications that do not create this dependency automatically, it is recommended you use the following steps:

1. Create the application/parent resource hierarchy. Note: Do not extend the resource hierarchy to a backup server at this time. You will receive a warning message when you elect not to extend your hierarchy, but in this particular situation, it is the proper action to take.

2. Create the IP resource hierarchy. Note: Do not extend the IP resource hierarchy to a backup server at this time. You will receive a warning message when you elect not to extend your hierarchy, but in this particular situation, it is the proper action to take.

3. Create the parent/child dependency between the parent application resource hierarchy and the IP resource hierarchy using the Create Resource Dependency configuration task (see the LifeKeeper for Linux topic, Creating a Resource Dependency.

4. Finally, extend the application resource hierarchy to the backup server. Since the dependency has already been created, the dependent IP resource instance will also be extended to the backup server as part of the parent application resource hierarchy.

The steps outlined above save you from performing one extra extension (i.e. the extension of the IP resource to the backup server).