General

• Overview
• Single Node Setup
• Cluster Setup
• Hadoop Commands Reference
• FileSystem Shell
• Hadoop Compatibility
• Interface Classification
• FileSystem Specification

Common

• CLI Mini Cluster
• Native Libraries
• Proxy User
• Rack Awareness
• Secure Mode
• Service Level Authorization
• HTTP Authentication
• Hadoop KMS
• Tracing

HDFS

• HDFS User Guide
• HDFS Commands Reference
• High Availability With QJM
• High Availability With NFS
• Federation
• ViewFs Guide
• HDFS Snapshots
• HDFS Architecture
• Edits Viewer
• Image Viewer
• Permissions and HDFS
• Quotas and HDFS
• HFTP
• C API libhdfs
• WebHDFS REST API
• HttpFS Gateway
• Short Circuit Local Reads
• Centralized Cache Management
• HDFS NFS Gateway
• HDFS Rolling Upgrade
• Extended Attributes
• Transparent Encryption
• HDFS Support for Multihoming
• Archival Storage, SSD & Memory
• Memory Storage Support

MapReduce

• MapReduce Tutorial
• MapReduce Commands Reference
• Compatibilty between Hadoop 1.x and Hadoop 2.x
• Encrypted Shuffle
• Pluggable Shuffle/Sort
• Distributed Cache Deploy

MapReduce REST APIs

• MR Application Master
• MR History Server

YARN

• Overview
• YARN Architecture
• Capacity Scheduler
• Fair Scheduler
• ResourceManager Restart
• ResourceManager HA
• Node Labels
• Web Application Proxy
• YARN Timeline Server
• Writing YARN Applications
• YARN Commands
• NodeManager Restart
• YARN Application Security
• DockerContainerExecutor
• Using CGroups
• Secure Containers
• Registry

YARN REST APIs

• Introduction
• Resource Manager
• Node Manager
• Timeline Server

Hadoop Compatible File Systems

• Amazon S3
• Azure Blob Storage
• OpenStack Swift

Auth

• Overview
• Examples
• Configuration
• Building

Tools

• Hadoop Streaming
• Hadoop Archives
• DistCp
• GridMix
• Rumen
• Scheduler Load Simulator

Reference

• Release Notes
• API docs
• Common CHANGES.txt
• HDFS CHANGES.txt
• MapReduce CHANGES.txt
• YARN CHANGES.txt
• Metrics

Configuration

• core-default.xml
• hdfs-default.xml
• mapred-default.xml
• yarn-default.xml
• Deprecated Properties

Apache Hadoop 2.7.5

Apache Hadoop 2.7.5 is a minor release in the 2.x.y release line, building upon the previous stable release 2.7.4.

Here is a short overview of the major features and improvements.

• Common

  • Multiple unit test failures fixed across all subprojects.
  • Optimized UGI group handling.
  • Improved reading of compressed splits.

• HDFS

  • Fixed bugs to prevent NameNode from crashing due to NPE and full GC.
  • NameNode performance improvements for path handling.
  • Namesystem metrics improvements.

• YARN

  • Resource Manager improvements and bug fixes.
  • Handling Node Manager timeouts during shuffle stage.

Getting Started

The Hadoop documentation includes the information you need to get started using Hadoop. Begin with the Single Node Setup which shows you how to set up a single-node Hadoop installation. Then move on to the Cluster Setup to learn how to set up a multi-node Hadoop installation.