unclean.leader.election.enable — Kafka Broker Configuration
Indicates whether to enable replicas not in the ISR set to be elected as leader as a last resort, even though doing so may result in data loss..
Description
Indicates whether to enable replicas not in the ISR set to be elected as leader as a last resort, even though doing so may result in data loss.
Default Values by Kafka Version
| Kafka Version | Default Value |
|---|---|
| 0.8.2 | true |
| 0.9.0 | true |
| 0.10.0 | true |
| 0.10.1 | true |
| 0.10.2 | true |
| 0.11.0 | false |
| 1.0 | false |
| 1.1 | false |
| 2.0 | false |
| 2.1 | false |
| 2.2 | false |
| 2.3 | false |
| 2.4 | false |
| 2.5 | false |
| 2.6 | false |
| 2.7 | false |
| 2.8 | false |
| 3.0 | false |
| 3.1 | false |
| 3.2 | false |
| 3.3 | false |
| 3.4 | false |
| 3.5 | false |
| 3.6 | false |
| 3.7 | false |
| 3.8 | false |
| 3.9 | false |
| 4.0 | false |
| 4.1 | false |
| 4.2 | false |
Tuning Recommendation
| Profile | Recommended | Why |
|---|---|---|
| broker / durability | false | The default false is correct and must not be changed for durability workloads. Enabling unclean leader election allows an out-of-sync replica to become leader, silently losing all messages the previous leader had that the new leader had not yet replicated. |
Related Configs
replica.lag.time.max.ms · default.replication.factor · min.insync.replicas
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