Apache ZooKeeper™

From Oxxus Wiki

It's a project with the main goal to develop and maintain an open source project with reliable distributed coordination.
Offers several kind of services like providing group services, distributed synchronization and maintaining configuration information, that can be used in some form or at entire different distributed application.

Starting up

It's available as an binary release from download mirror.
Can be started at single server hosted at desired hosting provider, or even at small cluster.

Server, or hosting, requirements listed here have to be met in order to have Apache ZooKeeper™ run as Standalone server Running ZooKeeper™ as Standalone server is suitable in development phase but when it comes to production state then ZooKeeper™ has to be run in the replicated mode.

Basic Overview

Being very simple and fast, it represents basis for construction of more complicated services like synchronization.

Simple API, which provides few operations like:

• create creates a node at a location in the tree
  
• delete deletes a node
  
• exists tests if a node exists at a location
  
• get data reads the data from a node
  
• set data writes data to a node
  
• get children retrieves a list of children of a node
  
• sync waits for data to be propagated

High level of components implementation is provided, while designed to offer high performance with high reliability

With all benefits presented above, ZooKeeper™ is used in many industrial applications, for example, as the coordination and failure recovery service for Yahoo! Message Broker. Many Yahoo advertising systems relays on ZooKeeper™ services.