You started a consumer, but the ApsaraMQ for Kafka console shows no subscriptions on the Subscriptions tab of the Topic Details page or the Consumer Status tab of the Group Details page. This happens for one of two reasons.
The consumer failed to connect
If the consumer settings are invalid or a network issue prevents the consumer from reaching the broker, no subscription registers with the cluster and the console has nothing to display.
To resolve this:
Check your consumer configuration against Best practices for consumers. Common mistakes include incorrect
bootstrap.servers, missing authentication parameters, or mismatchedgroup.idvalues.Verify network connectivity between your consumer and the ApsaraMQ for Kafka endpoint. If the connection fails, see What do I do if the attempt to ping the endpoint of ApsaraMQ for Kafka failed?.
You used assign mode without committing offsets
Kafka consumers consume from topics in two ways:
subscribemode -- The consumer joins the consumer group through the group coordinator. The broker tracks this subscription and displays it in the console automatically.assignmode -- The consumer manually specifies which partitions to read from, bypassing group coordination. The broker has no record of this assignment unless the consumer explicitly commits its offset.
If you used assign mode, the console cannot display subscription data until offsets are committed. To fix this, commit the consumer offset. For details, see Commit consumer offsets.