Zookeeper Series VII-recognize zookeeper from remote calls

Http://www.csdn.net/article/2014-01-02/2817944-zookeeper

In the learning process of Hadoop, zookeeper is a technology that confuses many beginners, and the remote invocation service is a very suitable scenario for zookeeper applications, where the remote Invocation service architecture is designed, and the zookeeper application scenario is described in detail.

Zookeeper Technical explanation

In the remote service zookeeper is used in the remote call management component, while the service caller is the zookeeper client, the remote call management component is also the core of the remote Call service, if the remote call management component hangs at runtime, then the entire application will also be unavailable. Therefore, the remote invocation of the management component must be reliable, and this reliability requirement is even higher than the level of reliability of the service provider and service callers, so the design of the remote call management component must be distributed, and must be reliable and distributed.

Remote Call management component is a fully compliant zookeeper scenario application or a standard zookeeper application, in order to facilitate later discussion, here I further explain the function of remote call management component. From the previous narrative, we know that the central role of the remote call Management component is the configuration information that stores the service provider and the service caller's communication, such as the IP address and port of the storage service provider, and the service class of the service provider. It also records the IP address and port number of the service caller (this information is entered by the Web Management system that invokes the management component remotely) and the control relationship between the service caller and the service provider. For service providers, the remote Call Management component also provides a heartbeat mechanism to detect the health state of the service provider, and if a remote call to the management component discovers that a service provider has problems with some servers, it updates the service provider's configuration information in a timely manner and pushes these changes to the service caller in a timely fashion. From the point of view of the configuration information store, the remote call management component is actually a Remote Storage configuration information system, and the heartbeat mechanism and push mechanism this is an observer pattern, and these functions are distributed environment functions, need high reliability. Zookeeper most typical application is to be able to do distributed application configuration services, the specific point is to write to our usual configuration file, to the distributed system also need a separate system to complete, and is a dynamic configuration services.

Zookeeper Series VII-recognize zookeeper from remote calls