Page History

...

Consumers with the default group id ("") that use assign(...) to consume from hand-picked partitions will not be able to commit offsets. If they attempt an offset commit they will receive an error. A new error will be introduced in org.apache.kafka.common.protocol.Errors for this purpose.

    ...
    ILLEGAL_OFFSET_COMMIT(72, "The standalone consumer belonging to a group with default id (\"\") is not allowed to commit offsets",
        new ApiExceptionBuilder() {
            @Override
            public ApiException build(String message) {
                return new IllegalOffsetCommitException(message);
            }
    }
    ...

Stand-alone consumers using the default group id will have to seek to an offset before start fetching; or the auto.offset.commit value will be used to determine the starting point of fetch. They will no longer be able to start from a previously committed fetch position.

...