Now, the client will have another endpoint ‘/bus-refresh'. Calling this endpoint will cause:

get the latest configuration from the config server and update its configuration annotated by @RefreshScope

send a message to AMQP exchange informing about refresh event

all subscribed nodes will update their configuration as well 

Spring Cloud Bus uses lightweight message broker to link distributed system nodes. The primary usage is to broadcast configuration changes or other management information. We can think about it as a distributed Actuator.

The project uses AMQP broker as the transport, but Apache Kafka or Redis can be utilized instead of RabbitMQ. Other transports are not supported yet.

https://www.baeldung.com/spring-cloud-bus