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• JOC Cockpit can be operated in the following modes:
  • single instance,
  • active-passive clustered instances with one active instance and any number of standby instances.
• Cluster Service
  • manages a number of Background Services:
    • Monitor Service: checks execution history for events that users should be notified about.
    • Restart Service: reruns pending deployments and performs synchronization with a Controller.
    • Cleanup Service: purges the database, e.g. to limit the size of the history.
    • History Service: retrieves execution results and logs from a Controller instance.
    • Daily Plan Service: creates and submits orders to connected Controllers.
  • guarantees service execution:
    • checks the cluster health status of any connected JOC Cockpit instances,
    • performs a fail-over operation in case that the Active JOC Cockpit instance fails.
• Event Bus Service
  • An event bus manages communication between JOC Cockpit services:
    • events are published in a producer/consumer (publish/subscribe) model,
    • events are asynchronous, i.e. a service does not rely on immediate responses,
    • events are not persistent, i.e. they are removed after being consumed or after some timeout,
    • events are considered informational for the user interface that displays current data.
• Proxy Service
  • On start-up the Proxy will retrieve a snapshot of the Controller's journal and will subsequently receive any events fired by a Controller.
  • The Proxy implements an event queue that can be subscribed to by a number of consumers, e.g. by Background Services and by the GUI.

Further Resources