##### 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 0.23.8 - 2013-06-05

### BUG FIXES:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
MAPREDUCE-4383 | HadoopPipes.cc needs to include unistd.h | Minor | pipes | Andy Isaacson | Andy Isaacson
YARN-71 | Ensure/confirm that the NodeManager cleans up local-dirs on restart | Critical | nodemanager | Vinod Kumar Vavilapalli | Xuan Gong
HDFS-4690 | Namenode exits if entering safemode while secret manager is edit logging | Critical | namenode, security | Daryn Sharp | Daryn Sharp
MAPREDUCE-5065 | DistCp should skip checksum comparisons if block-sizes are different on source/target. | Major | distcp | Mithun Radhakrishnan | Mithun Radhakrishnan
YARN-476 | ProcfsBasedProcessTree info message confuses users | Minor | . | Jason Lowe | Sandy Ryza
HDFS-4699 | TestPipelinesFailover#testPipelineRecoveryStress fails sporadically | Major | test | Chris Nauroth | Chris Nauroth
MAPREDUCE-5147 | Maven build should create hadoop-mapreduce-client-app-VERSION.jar directly | Major | mrv2 | Robert Parker | Robert Parker
HADOOP-9469 | mapreduce/yarn source jars not included in dist tarball | Major | . | Thomas Graves | Robert Parker
YARN-363 | yarn proxyserver fails to find webapps/proxy directory on startup | Major | . | Jason Lowe | Kenji Kikushima
MAPREDUCE-5168 | Reducer can OOM during shuffle because on-disk output stream not released | Critical | mrv2 | Jason Lowe | Jason Lowe
HDFS-4477 | Secondary namenode may retain old tokens | Critical | security | Kihwal Lee | Daryn Sharp
YARN-690 | RM exits on token cancel/renew problems | Blocker | resourcemanager | Daryn Sharp | Daryn Sharp
MAPREDUCE-4927 | Historyserver 500 error due to NPE when accessing specific counters page for failed job | Major | jobhistoryserver | Jason Lowe | Ashwin Shankar
HDFS-4835 | Port trunk WebHDFS changes to branch-0.23 | Critical | webhdfs | Robert Parker | Robert Parker
HDFS-3875 | Issue handling checksum errors in write pipeline | Critical | datanode, hdfs-client | Todd Lipcon | Kihwal Lee
HDFS-4807 | DFSOutputStream.createSocketForPipeline() should not include timeout extension on connect | Major | . | Kihwal Lee | Cristina L. Abad
HDFS-4714 | Log short messages in Namenode RPC server for exceptions meant for clients | Major | namenode | Kihwal Lee | Kihwal Lee
HADOOP-9614 | smart-test-patch.sh hangs for new version of patch (2.7.1) | Major | . | Ravi Prakash | Ravi Prakash
MAPREDUCE-5211 | Reducer intermediate files can collide during merge | Blocker | mrv2 | Jason Lowe | Jason Lowe
HADOOP-9504 | MetricsDynamicMBeanBase has concurrency issues in createMBeanInfo | Critical | metrics | Liang Xie | Liang Xie
MAPREDUCE-5059 | Job overview shows average merge time larger than for any reduce attempt | Major | jobhistoryserver, webapps | Jason Lowe | Omkar Vinit Joshi

### TESTS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
HADOOP-9222 | Cover package with org.apache.hadoop.io.lz4 unit tests | Major | . | Vadim Bondarev | Vadim Bondarev
HADOOP-9233 | Cover package org.apache.hadoop.io.compress.zlib with unit tests | Major | . | Vadim Bondarev | Vadim Bondarev
MAPREDUCE-5015 | Coverage fix for org.apache.hadoop.mapreduce.tools.CLI | Major | . | Aleksey Gorshkov | Aleksey Gorshkov

### SUB-TASKS:

JIRA | Summary | Priority | Component | Reporter | Contributor
--- | --- | --- | --- | --- | ---
YARN-548 | Add tests for YarnUncaughtExceptionHandler | Major | . | Vadim Bondarev | Vadim Bondarev