- The wording is important: a Controller can be operated as a Standalone Controller instance or as a JS7 - Controller Cluster. The term Controller Instance refers to a Standalone Controller instance or to a Controller Cluster member instance.
- The outage of a Controller instance will not necessarily stop execution of workflows with Agents.
- However, if a workflow includes jobs that are executed with different Agents then the workflow will not be completed and will be put on hold as switching of Agents during workflow execution is performed by the Controller.
- You can find further details in the JS7 - Workflow Execution with Controllers and Agents article.
- Testing by SOS includes performing tests for a scenario when a Controller is not available for 24 hours and the Agent executes any scheduled orders. Once the Controller instance is started again then job execution results are updated to the JOC Cockpit History and become visible with the GUI.
- For more information about the behavior in the event of an outage see JS7 - FAQ - What happens to workflows in case of outage of a Controller
When operating a Controller Cluster then an automated fail-over takes place should the active Controller instance fails. A fail-over typically occurs within 3-5s. If the standby Controller instance fails then this does not affect the active Controller instance. Running a JS7 high availability cluster provides the relaxed option of not to have to take immediate action if a single instance fails. However, if users intend to make a failed Controller Cluster member instance available immediately then the steps outlined below will also apply for the failed instance.
The troubleshooting hints listed below are intended for users operating a Standalone Controller, the steps explained are not required for users operating a Controller Cluster.