THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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Name | Type | Default | Importance | Doc |
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| Whether to enable exactly-once support for source connectors in the cluster by writing source records and their offsets in a Kafka transaction, and by proactively fencing out old task generations before bringing up new ones. Note that this must be enabled on every worker in a cluster in order for exactly-once delivery to be guaranteed, and that some source connectors may still not be able to provide exactly-once delivery guarantees even with this support enabled. Permitted values are "disabled", "preparing", and "enabled". In order to safely enable exactly-once support for source connectors, all workers in the cluster must first be updated to use the "preparing" value for this property. Once this has been done, a second update of all of the workers in the cluster should be performed to change the value of this property to "enabled". |
And four new per-connector configuration properties will be added:
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When exactly.once.source.enabled is set to true , workers will preemptively stop source tasks when and a new set of task configurations for their a connector is detected, then workers will preemptively stop source tasks for that connector. In greater detail:
When a rebalance is triggered, before rejoining the cluster group, workers will preemptively stop all tasks of all source connectors for which task configurations are present in the config topic after the latest task count record. This step is not necessary to preserve exactly-once delivery guarantees, but should provide a reasonable opportunity for tasks to shut down gracefully before being forcibly fenced out.
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