Consider that loss of a Controller's journal includes that
- any scheduling objects such as workflows have to be re-deployed,
- any orders of the Daily Plan have to be re-submitted,
- any currently running orders are lost and no information about orders and the execution status of jobs is available.
See JS7 - FAQ - What happens to workflows in case of outage of a Controller?
Use of a Controller cluster will leverage such a situation as the Secondary Controller instance operates a synchronized copy of the journal and will pick up operations immediately during fail-over (3-5s). The failed Primary Controller instance can be started later on and will automatically synchronize with the Secondary Controller instance's journal.

Initial Operation

Ongoing Operation

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