##### 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 2.8.5 - Unreleased (as of 2018-09-02)

### IMPROVEMENTS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-13738 | DiskChecker should perform some disk IO | Major | . | Arpit Agarwal | Arpit Agarwal
HADOOP-15394 | Backport PowerShell NodeFencer HADOOP-14309 to branch-2 | Minor | . | Íñigo Goiri | Íñigo Goiri
HADOOP-15441 | Log kms url and token service at debug level. | Minor | . | Wei-Chiu Chuang | Gabor Bota
HADOOP-15486 | Make NetworkTopology#netLock fair | Major | net | Nanda kumar | Nanda kumar
HADOOP-15449 | Increase default timeout of ZK session to avoid frequent NameNode failover | Critical | common | Karthik Palanisamy | Karthik Palanisamy
HDFS-13602 | Add checkOperation(WRITE) checks in FSNamesystem | Major | ha, namenode | Erik Krogen | Chao Sun
HADOOP-15689 | Add “*.patch” into .gitignore file of branch-2 | Major | . | Rui Gao | Rui Gao
YARN-8051 | TestRMEmbeddedElector#testCallbackSynchronization is flakey | Major | test | Robert Kanter | Robert Kanter

### BUG FIXES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-15121 | Encounter NullPointerException when using DecayRpcScheduler | Major | . | Tao Jie | Tao Jie
HDFS-10803 | TestBalancerWithMultipleNameNodes#testBalancing2OutOf3Blockpools fails intermittently due to no free space available | Major | . | Yiqun Lin | Yiqun Lin
HDFS-12828 | OIV ReverseXML Processor fails with escaped characters | Critical | hdfs | Erik Krogen | Erik Krogen
HADOOP-15396 | Some java source files are executable | Minor | . | Akira Ajisaka | Shashikant Banerjee
YARN-8232 | RMContainer lost queue name when RM HA happens | Major | resourcemanager | Hu Ziqian | Hu Ziqian
HDFS-13581 | DN UI logs link is broken when https is enabled | Minor | datanode | Namit Maheshwari | Shashikant Banerjee
HADOOP-15450 | Avoid fsync storm triggered by DiskChecker and handle disk full situation | Blocker | . | Kihwal Lee | Arpit Agarwal
HADOOP-15473 | Configure serialFilter in KeyProvider to avoid UnrecoverableKeyException caused by JDK-8189997 | Critical | kms | Gabor Bota | Gabor Bota
YARN-8444 | NodeResourceMonitor crashes on bad swapFree value | Major | . | Jim Brennan | Jim Brennan
HADOOP-15548 | Randomize local dirs | Minor | . | Jim Brennan | Jim Brennan
YARN-8383 | TimelineServer 1.5 start fails with NoClassDefFoundError | Blocker | . | Rohith Sharma K S | Jason Lowe
YARN-8473 | Containers being launched as app tears down can leave containers in NEW state | Major | nodemanager | Jason Lowe | Jason Lowe
YARN-8515 | container-executor can crash with SIGPIPE after nodemanager restart | Major | . | Jim Brennan | Jim Brennan
YARN-8421 | when moving app, activeUsers is increased, even though app does not have outstanding request | Major | . | kyungwan nam |
HADOOP-15614 | TestGroupsCaching.testExceptionOnBackgroundRefreshHandled reliably fails | Major | . | Kihwal Lee | Weiwei Yang
HADOOP-15637 | LocalFs#listLocatedStatus does not filter out hidden .crc files | Minor | fs | Erik Krogen | Erik Krogen
HADOOP-15674 | Test failure TestSSLHttpServer.testExcludedCiphers with TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 cipher suite | Major | common | Gabor Bota | Szilard Nemeth
YARN-8640 | Restore previous state in container-executor after failure | Major | . | Jim Brennan | Jim Brennan
HADOOP-14314 | The OpenSolaris taxonomy link is dead in InterfaceClassification.md | Major | documentation | Daniel Templeton | Rui Gao
YARN-8649 | NPE in localizer hearbeat processing if a container is killed while localizing | Major | . | lujie | lujie

### SUB-TASKS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-4781 | Support intra-queue preemption for fairness ordering policy. | Major | scheduler | Wangda Tan | Eric Payne
HDFS-13281 | Namenode#createFile should be /.reserved/raw/ aware. | Critical | encryption | Rushabh S Shah | Rushabh S Shah