- When Eureka Client starts sending its information services to Eureka Server. Then 2 other service information call the current server node, save in the Eureka Client. When the service call other services among each other, after the service information (e.g. service address, port, etc.) in the Eureka Client in step 3. The call information services directly. (Note: the service invocation by calling http (s))
- When a service need only call other services, it does not provide its own service calls. After Eureka Client will start to pull the other service information Eureka Server, when you need to call for information in the local cache Eureka Client, call the service.
- Eureka Client sends a heartbeat to the Eureka Serve (every 30 seconds by default) to renew services. If the client can not continue to renew, then it is removed from the registry server in about 90 seconds. Registration and renewal information is copied to Eureka Serve all nodes in the cluster. In order to ensure current service still "alive" can be called.
- Eureka Client from any district can find registry information (occurs every 30 seconds), in order to ensure that calls to the service is "alive." And when a service is updated or a new add to the mix, you can also call to the new service.
Eureka Server
- Registration service: when the individual micro service starts, it will register their information (such as service and network information) to Eureka Server through Eureka Client, Eureka Server will store information on this service.
- Service information: at the service when consumers call service, local Eureka Client is not the case, Eureka Server to pull information.
- Service management: to maintain information about the services provided by Eureka Client's Cancel, heart rate monitor, renew, etc. to ensure that the services are available, and update services.
- Information Synchronization: Each Eureka Server is also the Eureka Client, between multiple Eureka Server service registry synchronization is accomplished by way of P2P replication.
Eureka Client
- Eureka Client is a Java client for simplifying interaction with the Eureka Server. And the current micro-management services, while providing service provider information for the current micro-services.
- Eureka Client will pull, and update information in the cache Eureka Server. Even if all of Eureka Server nodes shoot down, service consumers can still use the information in the cache to find the service provider.
Eureka Client service starts after the micro, periodically sends a heartbeat to the Eureka Server (default period is 30 seconds) to renew their information. If Eureka Server does not receive a heartbeat micro service node within a certain time, Eureka Server will log off the micro-service node (default 90 seconds).