Acknowledgment modes (acks=0, 1, all) in Kafka - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does acks=0 mean in Kafka producer configuration?

acks=0 means the producer does not wait for any acknowledgment from the broker after sending a message. It sends the message and moves on immediately.

This is the fastest mode but risks message loss if the broker fails.

beginner

Explain acks=1 in Kafka producer settings.

acks=1 means the producer waits for acknowledgment from the leader broker only.

The leader confirms it received the message, but followers might not have replicated it yet.

This balances speed and reliability.

beginner

What does acks=all (or acks=-1) guarantee in Kafka?

acks=all means the producer waits for acknowledgment from all in-sync replicas.

This ensures the message is fully replicated and is the safest mode against data loss.

It is slower but more reliable.

beginner

Which acknowledgment mode offers the fastest message sending but the least reliability?

acks=0 offers the fastest sending because the producer does not wait for any confirmation.

However, it risks losing messages if the broker fails before storing them.

intermediate

Why might you choose acks=all despite its slower speed?

You choose acks=all to ensure maximum data safety.

It waits for all replicas to confirm the message, reducing the chance of data loss even if some brokers fail.

What does acks=0 mean in Kafka?

A Producer waits for leader acknowledgment only

B Producer retries sending messages indefinitely

C Producer waits for all replicas acknowledgment

D Producer does not wait for any acknowledgment

acks=0 means the producer sends messages without waiting for any confirmation from brokers.

Which acks setting waits for the leader broker's confirmation only?

A acks=all

B acks=0

C acks=1

D acks=-1

acks=1 waits for the leader broker to confirm the message.

What is the main advantage of acks=all?

A Waits for all in-sync replicas to confirm

B No message loss risk

C No acknowledgments needed

D Fastest message sending

acks=all waits for all in-sync replicas to confirm, ensuring full replication.

If you want the fastest sending speed and can tolerate some message loss, which acks value should you use?

A acks=all

B acks=0

C acks=1

D acks=-1

acks=0 does not wait for any acknowledgment, so it is the fastest but least reliable.

What does acks=-1 mean in Kafka?

A Same as acks=all

B Same as acks=1

C Same as acks=0

D Disables acknowledgments

acks=-1 is an alias for acks=all, waiting for all replicas to confirm.

Describe the differences between acks=0, acks=1, and acks=all in Kafka producer configuration.

Think about how much the producer waits before considering a message sent.

Why would a Kafka producer choose acks=all over acks=1 or acks=0?

Consider what happens if a broker fails after receiving a message.