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Kafka Error `GROUP_SUBSCRIBED_TO_TOPIC`

Error code 86 · Non-retriable Consumer

Deleting offsets of a topic is forbidden while the consumer group is actively subscribed to it.

Common Causes

kafka-consumer-groups.sh --delete-offsets was called for a topic while at least one consumer in the group still has an active subscription to that topic
Attempting to reset offsets for a topic in a group that has live consumers — even a single connected consumer blocks the operation
CI/CD pipeline tried to reset consumer group offsets without first stopping the consuming application

Solutions

Stop all consumers in the group before resetting offsets — verify with kafka-consumer-groups.sh --describe and confirm STATE is Empty before proceeding
Use --execute only after confirming zero active members; use --dry-run first to validate the reset plan without risk
If you cannot stop the running group, do not force a reset against the active group; use a new group.id for replay or schedule the reset during a maintenance window

Diagnostic Commands

# Check consumer group state and members
kafka-consumer-groups.sh --bootstrap-server localhost:9092 --describe --group <group-id> | grep -E 'STATE|CONSUMER-ID'

# Show active members in the consumer group
kafka-consumer-groups.sh --bootstrap-server localhost:9092 --describe --group <group-id> --members

Related APIs

This error can be returned by: OffsetDelete

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