Setting auto.offset.reset=earliest causes the consumer to read from?

Setting auto.offset.reset=earliest causes the consumer to read from?

• A. End of the log
• B. Beginning of the log
• C. From the last committed offset
• D. From the next offset after the consumer starts

Answer: (B)

The setting auto.offset.reset governs where a consumer starts when there is no previously committed offset for a partition. When you choose earliest, the consumer begins at the beginning of the log, i.e., the smallest available offset, so you read all messages from the start. If there is a previously committed offset for your consumer group, Kafka will resume from that offset regardless of this setting. If the committed offset is missing or out of range, auto.offset.reset then kicks in to determine where to start, which for earliest means from the very beginning. Beginning from the end of the log or from a committed offset is not what earliest implies in the no-offset-scenario, and starting from the next offset after the consumer starts isn’t how Kafka determines the starting point.

The setting auto.offset.reset governs where a consumer starts when there is no previously committed offset for a partition. When you choose earliest, the consumer begins at the beginning of the log, i.e., the smallest available offset, so you read all messages from the start. If there is a previously committed offset for your consumer group, Kafka will resume from that offset regardless of this setting. If the committed offset is missing or out of range, auto.offset.reset then kicks in to determine where to start, which for earliest means from the very beginning. Beginning from the end of the log or from a committed offset is not what earliest implies in the no-offset-scenario, and starting from the next offset after the consumer starts isn’t how Kafka determines the starting point.