Which command starts consuming messages in a consumer group named 'my-first-consumer-group'?

Which command starts consuming messages in a consumer group named 'my-first-consumer-group'?

• A. bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic my-first-topic --group my-first-consumer-group
• B. bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic my-first-topic
• C. bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic my-first-topic --group other-group --from-beginning
• D. bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic my-first-topic --group my-first-consumer-group --from-beginning

Answer: (D)

Joining a specific consumer group and choosing where to start reading are the key points. To participate in a named group, you must specify that group with the options tied to the consumer, and to guarantee you read from the very start of the topic, you add the option that starts from the earliest offset. The best command does both: it connects to the broker, subscribes to the topic, attaches to the exact consumer group named my-first-consumer-group, and explicitly starts from the beginning of the log. This ensures you don’t reuse any previously committed offsets and you begin with the oldest available messages for that group. If you omit the group, the consumer would not join your named group and would create an anonymous or different group, so it wouldn’t be part of my-first-consumer-group. If you include a different group, you’d be joining another group, not the one you specified. And if you omit the option to start from the beginning, the consumer would resume from where that group last left off, which might miss earlier messages.

Joining a specific consumer group and choosing where to start reading are the key points. To participate in a named group, you must specify that group with the options tied to the consumer, and to guarantee you read from the very start of the topic, you add the option that starts from the earliest offset.

The best command does both: it connects to the broker, subscribes to the topic, attaches to the exact consumer group named my-first-consumer-group, and explicitly starts from the beginning of the log. This ensures you don’t reuse any previously committed offsets and you begin with the oldest available messages for that group.

If you omit the group, the consumer would not join your named group and would create an anonymous or different group, so it wouldn’t be part of my-first-consumer-group. If you include a different group, you’d be joining another group, not the one you specified. And if you omit the option to start from the beginning, the consumer would resume from where that group last left off, which might miss earlier messages.