Question: I have 3 consumers subscribed to a Kafka topic.
A producer publishes 1 message to a topic.

How can I make sure that the message is replicated internally in Kafka and is then consumed by all 3 consumers?

One way would be to not commit the message, but then messages will keep on piling up in the topic.

Answer: 
You should set 3 different **consumer group** (with different id) for the 3 consumers.

> 
> Consumers label themselves with a consumer group name, and each record
>  published to a topic is delivered to one consumer instance within each
>  subscribing consumer group. Consumer instances can be in separate
>  processes or on separate machines.
> 
> 
> If all the consumer instances have the same consumer group, then the
>  records will effectively be load balanced over the consumer instances.
> 
> 
> If all the consumer instances have different consumer groups, then
>  each record will be broadcast to all the consumer processes.
> 
> 
> 

from <https://kafka.apache.org/documentation/>
The only thing you have to do is to assign different group ids to every consumer