Backends

    Data storage is an exclusive feature of EMQ X Enterprise.

    1. PUB publishes a message;
    2. Backend records this message in DB;
    3. SUB subscribes to a topic;
    4. Backend retrieves the messages of this topic from DB;
    5. Messages are sent to SUB;

    1. PUB publishes a message;
    2. Backend records the message in DB;
    3. SUB1 and SUB2 subscribe to a topic;
    4. Backend retrieves the messages of this topic;
    5. Messages are sent to SUB1 and SUB2;

    EMQ X Persistence supports subscription by broker. When a client goes online, the persistence module loads the subscriptions of the client from Redis or Databases.