Zookeeper is a distributed coordination system to provide consistent service applications to achieve, domain name maintenance, distributed services. It Fast Paxos algorithm based on the Zab agreement, through the election leader, and only leader to submit proposals to address the problem that many members live lock Paxos algorithm to submit proposals arising from mutually exclusive. Passing leader status change by Zab agreement to ensure that leader and follow and consistency. Zookeeper are generally clustered mode, there is no single point of failure thus ensuring reliability.
dubbo, kafka, hbase, solr and many other open source projects have used the Zookeeper. Zookeeper provide consistency to solve the problem of the most basic atomic operation, but coordination of services need to develop themselves to achieve, and native client API does not work well, so there Curator to solve this problem.
Compared with stand-alone application, the introduction of distributed systems is dependent on the network communication, and therefore more network anomalies, data consistency issues to be addressed. Compared with the application within a function call, distributed RPC call one more timeout (unknown) state in addition to the cost of a failed state.
Copy (replica / copy) refers to a distributed system provides redundancy for data or services. Copy of the data is the only data loss means anomalies distributed system solutions. Another copy of a copy of the service, to provide some sort of index nodes of the same service, the service is generally not dependent on the local storage node, which is typically required data from other nodes. A copy of the agreement is consistent throughout the entire core of the theory of distributed systems.
Daily project business is limited, not involving a lot more skills extend to rely on self-study. Some interest groups can participate, learn from each other progress. Replay can help you review the course of the project, you can see where to do good, where do well, next time we can do better. Collision of ideas to inspire, add some more communities, listen to the experts, peers, seniors share their experiences to share some of the past, these are often not their own experiences, the book also can not be obtained.
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