Create a Resource Group Dependency

Use this task to manage and view the relationships (dependencies) among the resource groups within the selected cluster.

Dependencies between resource groups allow complex clusters that use multi-tired applications to be managed predictably and reliably. You can configure five types of dependencies among resource groups within a cluster:

Parent-Child

In this type of dependency, during resource group acquisition, the parent resource group on a node is acquired before the children resource groups are acquired. During resource group release, children resource groups are released before the parent resource group is released. The parent resource group must be online on any node in the cluster before children (dependent) resource groups can be activated on a node.

Parent resource group
Select the parent resource group from the list. The parent resource group provides services upon which a child resource group depends.
Child resource group
Select one or more child resource groups from the list. The child resource group depends on services that the parent resource group provides.

Online on same site

In this type of dependency, a location policy is established so that the selected resource groups are started and remains online on the same site.
Name
Indicates the name of the resource group.
HA Status
Indicates the status of the resource group.
Participating Nodes
Indicates the nodes that are part of the resource group.

Start After

In this type of dependency, during resource group acquisition, the target resource group on a node is acquired before the dependent resource group is acquired. The target resource group must be online on any node in the cluster before the dependent resource group can be activated on a node.

Target Resource Group
Select the target resource group from the list. The target resource group provides services upon which another resource group depends.
Resource group to start after the target resource group
Select the resource group from the list that you want to start after the target resource group starts.

Stop After

In this type of dependency, during resource group release, the target resource group on a node is released before the dependent resource group is released.

Target Resource Group
Select the target resource group from the list. The target resource group provides services upon which another resource group depends.
Resource groups to stop after the target resource group
Select the resource group from the list that you want to stop after the target resource group stops.

Online on Same Node

In this type of dependency, a set of two or more resource groups are acquired and brought online on the same node according to the startup policy and the availability of the node required. On fallback and fallover, the set of resource groups are processed simultaneously and brought online on the same target node using the fallover and fallback policy defined for these groups.

Resource groups to be online in the same node
Select two or more resource groups from the list to be acquired and brought online on the same node.

Online on Different Nodes

In this type of dependency, sets of resource groups are assigned High, Medium, and Low priority values, which are used in case there is contention for a given node at any point in time. Higher priority resource groups take precedence over lower priority groups at startup, fallover, and fallback. Each resource group in a set must have a different home node for startup. Only one Online On Different Nodes Dependency set is allowed per cluster.

Available resource groups
Available resource groups lists all discovered resource groups within the selected cluster that are available for this type of dependency. Select a resource group in the list, then click the > associated with the appropriate priority value to move the resource group to that priority list. Select resource groups in order of priority for handling failover in case of a node failure. You must select at least two resource groups.
High priority
Select one or more resource groups from the Available resource groups list to move to the High priority list. Resource groups in this list are to be acquired and brought online before lower priority resource groups.
Medium priority
Select one or more resource groups from the Available resource groups list to move to the Medium priority list. Resource groups in this list are to be acquired and brought online after the high priority groups and before low priority resource groups are brought online.
Selected low priority
Select one or more resource groups from the Available resource groups list to move to the Low priority list. Resource groups in this list are to be acquired and brought online after any higher priority or medium priority resource groups are brought online.