How does Kafka guarantee message integrity after a message is written on a disk?

Kafka ensures message immutability once data is written to disk. It guarantees that the message cannot be altered post-write, ensuring strong integrity.

From Kafka documentation:

“Kafka provides strong durability and immutability guarantees. Once a message is written and acknowledged, it cannot be modified.”

A → Incorrect: Offsets are immutable. Producers cannot overwrite messages.

C → Partially true for performance but not about message integrity.

D → Metadata changes do not affect message content or integrity.

Page Reference:

Kafka: The Definitive Guide, 1st Edition, Chapter 4, p. 122–123

Apache Kafka Documentation: Message Durability & Immutability

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