-If the "latest" option is used, a consumer can only get the last messages, and production needs to be ongoing in order to see the corresponding messages.
Open-source Kafka supports setting a timestamp field and type in a message. Currently, two timestamp types are supported:
CreateTimeindicates the local time on the client. As client time may vary from server time, please check whether the entered time is correct. If it differs too much from the current Beijing time, the CKafka service will not be able to expire and delete data promptly based on the normal message retention period, which may cause exceptional message heap.
LogAppendTimeindicates the time when a message is produced to the CKafka service, which is the CKafka server time and thus recommended.
The consumer group list in the CKafka console contains consumer group name, but no consumption details are displayed on the details page; for example, the consumer group CR has no details displayed in the figure below:
You should be able to see the names of all current consumer groups. If this is not the case, check whether the consumer clients are normal.
]$ bin/kafka-consumer-groups.sh --bootstrap-server 127.0.0.1:9092 --list CR
You will find that there are no details for this consumer group, which means that the consumer client did not use the
]$ bin/kafka-consumer-groups.sh --bootstrap-server 127.0.0.1:9092 --describe --group CR Note: This will not show information about old Zookeeper-based consumers.
consumerGroupmechanism to consume data, that is, the client did not submit consumption details to the server. As the server did not store the consumption data, no details will be displayed.
test1for consumption as shown below:
You should be able to see the normally displayed consumer group in the console, and you can run the
]$ bin/kafka-console-consumer.sh --bootstrap-server 127.0.0.1:9092 --from-beginning --topic test --group test1
--describecommand to view the details as shown below:
There are two data consumption modes in Kafka: consumer group mode and custom partition consumption mode.
When you add an ACL policy for a topic, the policy will prevent all other ineligible requests from accessing the topic, including those initiated by other Tencent Cloud services (e.g., log shipping in CLS, message dump in SCF, and component consumption in EMR) connected to CKafka. Therefore, before adding an ACL policy for a topic, you must determine whether the topic is being used in other scenarios through the service information or the monitoring information in the console; otherwise, problems with other linked features may occur.
In such cases, if you have to use an ACL policy, we recommend you produce messages to a new topic for permission grant instead of reusing the original topic.