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The Director Agent is contacted by the Controller for deployment of scheduling objects, for commands that change an order's state such as suspend, resume and cancel, and for reporting back the results of executing JS7 - Workflow Instructions if the Director Agent is not available.

The Director Agent can be used for clustered JS7 - File Watching by assigning a File Order Source the Agent Cluster. The active Director Agent instance will pick up file watching including situations when the active role switches as in case of fail-over and switch-over. 

Director Journal

The Director Agent holds a journal for storing:

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Director Agent Cluster

The Director Agent can can be operated as a single instance single instance and as a member in a passive from a passive Director Agent Cluster of two Director Agent instances.

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In a Director Agent Cluster one Director Agent instance holds the active role and the second instance holds the passive standby role.

If the Director Agent is operated as a cluster then the active instance synchronizes its journal with the standby instance. If the journals of both active and standby Director Agent instances are in sync then in case of fail-over (automatically) or switch-over (by user intervention) the Director Agent instances will switch the active roles.

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• Subagents are lightweight and do not operate a journal.
• Subagents are deployed to any number of servers in a network.
• Subagents are closely monitored by the Director Agents Agent using bi-directional heartbeats.

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• Subagents execute jobs on behalf of the Director Agent.
• They report back log output and the execution results of jobs to the Director Agent.
• If a Subagent fails then the Director Agent will can hand-over the job execution request to the next Subagent.
• A Subagent kills running jobs if the connection from the Director Agent is lost or if it is instructed by the Director Agent to suspend/kill or to cancel/kill an order.
  • This behavior is intended to prevent double job execution by more than one Subagent.
  • If the connection from the Director Agent can be re-established within a given timeout then the Subagent will continue to execute jobs.

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• A Subagent Cluster is specified by a Selection and Scheduling Mode:
  • The Subagent cluster can include a single Subagent, a number of Subagents or all Subagents.
  • The Scheduling Mode is one of fixed-priority or round-robin.
• Any number of Subagent Clusters can be configured reusing the same Subagents.

Functional Layer

Jobs in workflows are assigned a Subagent Cluster that includes a Selection and Scheduling Mode of Subagents: 

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Connections are unidirectional and are established:

• by the active Controller instances instance to the Director Agent instances,
• by the active Director Agent instances instance to the Subagents.

Workflow Execution

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