IBM Workload Scheduler Windows Cluster Enabler components

The IBM Workload Scheduler Windows Cluster Enabler consists of the following elements:
  • A utility to:
    • Install and remotely configure IBM Workload Scheduler on all the other nodes of the cluster
    • Install and configure the IBM Workload Scheduler cluster resource type for a given virtual server
  • An IBM Workload Scheduler Manager Custom Resource type to manage cluster events for IBM Workload Scheduler instances (new DLLs)
  • An IBM Workload Scheduler extension DLL to extend the Windows® Cluster Administration program
Figure 1. Main components of the IBM Workload Scheduler Cluster Enabler

Clusters enablement pack: components

The main component is the custom resource DLL. It has the following characteristics:
  • It can be brought online and taken offline
  • It can be managed in a cluster
  • It can be hosted (owned) by only one node at a time

As shown in Figure 1, the Cluster service communicates with the custom resource DLL through the resource monitor to manage resources. In response to a Cluster service request, the resource monitor calls the appropriate entry-point function in the custom resource DLL to check and control the resource state (possibly the IBM Workload Scheduler agent).

The custom resource DLL either performs the operation, signals the resource monitor to apply default processing (if any), or both. The custom resource DLL is responsible for providing entry-point implementations that serve the needs of the IBM Workload Scheduler resources.

The IBM Workload Scheduler Manager custom resource DLL provides the following entry-points (or services):
IsAlive
Determines if the IBM Workload Scheduler agent is currently active.
Offline
Performs a graceful shutdown of the IBM Workload Scheduler agent.
Online
Starts the IBM Workload Scheduler agent, links the agent to the network, and makes the resource available to the cluster.
Terminate
Performs an immediate shutdown of the resource.

The IBM Workload Scheduler Manager custom resource DLL is a bridge between the resource monitor (part of the Windows cluster service) and the IBM Workload Scheduler agent. The most important objective of the custom resource DLL is to understand the agent state and to bring it online or offline using the correct sequence of commands.