Kafka Multi-Region and Disaster Recovery
Two regions both write the same order and mirror to each other. After a network split, they disagree. The fix: One writer per key.
In this chapter
Pick an owner before mirroring
What breaks
Two regions both write the same order and mirror to each other. After a network split, they disagree.
Three ways to respond
- Newest timestamp wins: Clocks are not a merge rule.
- One home region per key (or a merge rule): One writer keeps one true order. (the fix)
- Same partition count = same offsets: Offsets are local to each cluster.
The fix: One home region per key (or a merge rule)
Cross-region replication is async. Decide ownership, failover, and how much data you can afford to lose (RPO) before an outage.
Remember: One writer per key.
More on Disaster recovery problems
- Kafka Simulator: Producers, Partitions and Consumer Groups
- How Uber, Netflix and Zomato Use Kafka: Real Architectures
- Kafka Interview Questions: 26 Real Production Problems
- Kafka vs a Message Queue: Why Events Stay After Reading
- Kafka Topics vs Partitions and Message Keys Explained
- Kafka Producer Batching: Async Send, linger.ms, batch.size
- Event-Driven Architecture with Kafka: Drop Sync Calls
- Kafka Fan-Out: One Event, Many Consumer Groups
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