resource_name /net/interfaces/lan/status/lan0 resource_polling_interval 60 resource_start automatic resource_up_value = up

NOTE: For a legacy package, specify the deferred resources again in the package control script, using the DEFERRED_RESOURCE_NAME parameter:

DEFERRED_RESOURCE_NAME[0]="/net/interfaces/lan/status/lan0"

DEFERRED_RESOURCE_NAME[1]="/net/interfaces/lan/status/lan1"

If a resource is configured to be AUTOMATIC in a legacy configuration file, you do not need to define DEFERRED_RESOURCE_NAME in the package control script.

About Package Dependencies

Starting in Serviceguard A.11.17, a package can have dependencies on other packages, meaning the package will not start on a node unless the packages it depends on are running on that node.

In Serviceguard A.11.17, package dependencies are supported only for use with certain applications specified by HP, such as the multi-node and system multi-node packages that HP supplies for use with Veritas Cluster File System (CFS) on systems that support it.

As of Serviceguard A.11.18, package dependency is no longer restricted; you can make a package dependent on any other package or packages running on the same cluster node, subject to the restrictions spelled out in Chapter 6, under dependency_condition (page 239).

As of A.11.19, Serviceguard adds two new capabilities: you can specify broadly where the package depended on must be running, and you can specify that it must be down. These capabilities are discussed later in this section under “Extended Dependencies” (page 141). You should read the next section, “Simple Dependencies” (page 137), first.

Simple Dependencies

A simple dependency occurs when one package requires another to be running on the same node. You define these conditions by means of the parameters dependency_condition and dependency_location, using the literal values UP and same_node, respectively. (For detailed configuration information, see the package parameter definitions starting with dependency_name” (page 238). For a discussion of complex dependencies, see “Extended Dependencies” (page 141).)

Make a package dependent on another package if the first package cannot (or should not) function without the services provided by the second, on the same node. For example, pkg1 might run a real-time web interface to a database managed by pkg2 on the same node. In this case it might make sense to make pkg1 dependent on pkg2.

In considering whether or not to create a simple dependency between packages, use the Rules for Simple Dependencies and Guidelines for Simple Dependencies that follow.

Rules for Simple Dependencies

Assume that we want to make pkg1 depend on pkg2.

Package Configuration Planning 137

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HP Serviceguard manual About Package Dependencies, Rules for Simple Dependencies