General

• Overview
• Single Node Setup
• Cluster Setup
• 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
• Credential Provider API
• Hadoop KMS
• Tracing

HDFS

• Architecture
• User Guide
• Commands Reference
• NameNode HA With QJM
• NameNode HA With NFS
• Federation
• ViewFs
• Snapshots
• Edits Viewer
• Image Viewer
• Permissions and HDFS
• Quotas and HDFS
• HFTP
• libhdfs (C API)
• WebHDFS (REST API)
• HttpFS
• Short Circuit Local Reads
• Centralized Cache Management
• NFS Gateway
• Rolling Upgrade
• Extended Attributes
• Transparent Encryption
• Multihoming
• Storage Policies
• Memory Storage Support
• Upgrade Domain
• DataNode Admin
• Router Federation

MapReduce

• Tutorial
• Commands Reference
• Compatibility with 1.x
• Encrypted Shuffle
• Pluggable Shuffle/Sort
• Distributed Cache Deploy
• Support for YARN Shared Cache

MapReduce REST APIs

• MR Application Master
• MR History Server

YARN

• Architecture
• Commands Reference
• Capacity Scheduler
• Fair Scheduler
• ResourceManager Restart
• ResourceManager HA
• Node Labels
• Web Application Proxy
• Timeline Server
• Timeline Service V.2
• Writing YARN Applications
• YARN Application Security
• NodeManager
• DockerContainerExecutor
• Running Applications in Docker Containers
• Using CGroups
• Secure Containers
• Registry
• Reservation System
• Graceful Decommission
• Opportunistic Containers
• YARN Federation
• Shared Cache

YARN REST APIs

• Introduction
• Resource Manager
• Node Manager
• Timeline Server
• Timeline Service V.2

Hadoop Compatible File Systems

• Amazon S3
• Azure Blob Storage
• OpenStack Swift

Auth

• Overview
• Examples
• Configuration
• Building

Tools

• Hadoop Streaming
• Hadoop Archives
• Hadoop Archive Logs
• DistCp
• GridMix
• Rumen
• Resource Estimator Service
• Scheduler Load Simulator
• Hadoop Benchmarking

Reference

• Changelog and Release Notes
• API docs
• Metrics

Configuration

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

Apache Hadoop 2.9.0

Apache Hadoop 2.9.0 is a minor release in the 2.x.y release line, building upon the previous stable release 2.8.2.

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

• Common

  • HADOOP Resource Estimator. See the user documentation for more details.

• HDFS

  • HDFS Router based federation. See the user documentation for more details.

• YARN

  • YARN Timeline Service v.2. See the user documentation for more details.
  • YARN Federation. See the user documentation for more details.
  • Opportunistic Containers. See the user documentation for more details.
  • YARN Web UI v.2. See the user documentation for more details.
  • Changing queue configuration via API (supported only on the Capacity Scheduler). See the user documentation for more details.
  • Update Resources and Execution Type of an allocated/running container (supported only on the Capacity Scheduler). See the user documentation for more details.

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.