1.Zookeeper concept
Zookeeper is a distributed coordination services , to provide coordinated services for users of distributed referenced
- A, zookeeper is distributed to other programs and services
- B, zookeeper itself is a distributed program (more than half as long as the surviving node, zk can provide services)
- Services cover C, zk provided: the main coordinator from the offline server node dynamic, unified configuration management, distributed shared lock, unified name of the service ...
D, although zk can provide a variety of services, but the underlying zk really only provides two functions:
Data management (storage, reading) submitted by the user
does not provide data monitoring service
2.ZK role
Zookeeper role cluster: Leader and Follower (Observer), as long as half of the cluster nodes survived the cluster will be able to provide services.