1. First, kafka will partition the received messages, and the messages of each topic (topic) have different partitions, so that on the one hand, the storage of messages will not be limited by the size of the storage space of a single server, on the other hand, messages The processing can also be parallelized on multiple servers.
2. Secondly, in order to ensure high availability, each partition will have a certain number of replicas. In this way, if some servers are unavailable, the server where the replica is located will take over to ensure the continuity of the application.
3. Then ensure the orderly consumption of messages within the partition.
4. Kafka also has the concept of consumer group, each partition can only be consumed by one consumer of the same group, but can be consumed by multiple groups.