##### General

- Overview
- Single Node Setup
- Cluster Setup
- Commands Reference
- FileSystem Shell
- Compatibility Specification
- Downstream Developer's Guide
- Admin Compatibility Guide
- 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
- Unix Shell Guide

##### HDFS

- Architecture
- User Guide
- Commands Reference
- NameNode HA With QJM
- NameNode HA With NFS
- Observer NameNode
- Federation
- ViewFs
- ViewFsOverloadScheme
- Snapshots
- Edits Viewer
- Image Viewer
- Permissions and HDFS
- Quotas and HDFS
- 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
- Synthetic Load Generator
- Erasure Coding
- Disk Balancer
- Upgrade Domain
- DataNode Admin
- Router Federation
- Provided Storage

##### 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
- Resource Model
- Node Labels
- Node Attributes
- Web Application Proxy
- Timeline Server
- Timeline Service V.2
- Writing YARN Applications
- YARN Application Security
- NodeManager
- Running Applications in Docker Containers
- Using CGroups
- Secure Containers
- Registry
- Reservation System
- Graceful Decommission
- Opportunistic Containers
- YARN Federation
- Shared Cache
- Using GPU
- Using FPGA
- Placement Constraints
- YARN UI2

##### YARN REST APIs

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

##### YARN Service

- Overview
- QuickStart
- Concepts
- Yarn Service API
- Service Discovery
- System Services

##### Submarine

- Index
- QuickStart
- Examples

##### Hadoop Compatible File Systems

- Aliyun OSS
- Amazon S3
- Azure Blob Storage
- Azure Data Lake 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
- Java API docs
- Unix Shell API
- Metrics

##### Configuration

- core-default.xml
- hdfs-default.xml
- hdfs-rbf-default.xml
- mapred-default.xml
- yarn-default.xml
- kms-default.xml
- httpfs-default.xml
- Deprecated Properties

# Apache Hadoop Changelog

## Release 2.6.2 - 2015-10-28

### INCOMPATIBLE CHANGES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-4087 | Followup fixes after YARN-2019 regarding RM behavior when state-store error occurs | Major | . | Jian He | Jian He

### IMPROVEMENTS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-3727 | For better error recovery, check if the directory exists before using it for localization. | Major | nodemanager | zhihai xu | zhihai xu

### BUG FIXES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-3194 | RM should handle NMContainerStatuses sent by NM while registering if NM is Reconnected node | Blocker | resourcemanager | Rohith Sharma K S | Rohith Sharma K S
MAPREDUCE-6334 | Fetcher#copyMapOutput is leaking usedMemory upon IOException during InMemoryMapOutput shuffle handler | Blocker | . | Eric Payne | Eric Payne
YARN-3554 | Default value for maximum nodemanager connect wait time is too high | Major | . | Jason Lowe | Naganarasimha G R
YARN-3780 | Should use equals when compare Resource in RMNodeImpl#ReconnectNodeTransition | Minor | resourcemanager | zhihai xu | zhihai xu
YARN-3802 | Two RMNodes for the same NodeId are used in RM sometimes after NM is reconnected. | Major | resourcemanager | zhihai xu | zhihai xu
YARN-2019 | Retrospect on decision of making RM crashed if any exception throw in ZKRMStateStore | Critical | . | Junping Du | Jian He
YARN-4005 | Completed container whose app is finished is not removed from NMStateStore | Major | . | Jun Gong | Jun Gong
MAPREDUCE-6454 | MapReduce doesn’t set the HADOOP_CLASSPATH for jar lib in distributed cache. | Critical | . | Junping Du | Junping Du
YARN-3896 | RMNode transitioned from RUNNING to REBOOTED because its response id had not been reset synchronously | Major | resourcemanager | Jun Gong | Jun Gong
MAPREDUCE-6497 | Fix wrong value of JOB_FINISHED event in JobHistoryEventHandler | Major | . | Shinichi Yamashita | Shinichi Yamashita
YARN-3798 | ZKRMStateStore shouldn’t create new session without occurrance of SESSIONEXPIED | Blocker | resourcemanager | Bibin A Chundatt | Varun Saxena

### SUB-TASKS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-4092 | RM HA UI redirection needs to be fixed when both RMs are in standby mode | Major | resourcemanager | Xuan Gong | Xuan Gong
YARN-4101 | RM should print alert messages if Zookeeper and Resourcemanager gets connection issue | Critical | yarn | Yesha Vora | Xuan Gong