README.md

Hadoop Ansible Playbook

Ansible playbook that installs a CDH 4.6.0 Hadoop cluster (running on Java 7, supported from CDH 4.4), with HBase, Hive, Presto for analytics, and Ganglia, Smokeping, Fluentd, Elasticsearch and Kibana for monitoring and centralized log indexing.

Follow @analytically. Browse the CI build screenshots.

Requirements

• Ansible 1.5 or later (pip install ansible)
• 6 + 1 Ubuntu 12.04 LTS/13.04/13.10 or Debian "wheezy" hosts - see ubuntu-netboot-tftp if you need automated server installation
• Mandrill username and API key for sending email notifications
• ansibler user in sudo group without sudo password prompt (see Bootstrapping section below)

Cloudera (CDH4) Hadoop Roles

If you're assembling your own Hadoop playbook, these roles are available for you to reuse:

• cdh_common - sets up Cloudera's Ubuntu repository and key
• cdh_hadoop_common - common packages shared by all Hadoop nodes
• cdh_hadoop_config - common configuration shared by all Hadoop nodes
• cdh_hadoop_datanode - installs Hadoop DataNode
• cdh_hadoop_journalnode - installs Hadoop JournalNode
• cdh_hadoop_mapreduce - installs Hadoop MapReduce
• cdh_hadoop_mapreduce_historyserver - installs Hadoop MapReduce history server
• cdh_hadoop_namenode - installs Hadoop NameNode
• cdh_hadoop_yarn_nodemanager - installs Hadoop YARN node manager
• cdh_hadoop_yarn_proxyserver - installs Hadoop YARN proxy server
• cdh_hadoop_yarn_resourcemanager - installs Hadoop YARN resource manager
• cdh_hadoop_zkfc - installs Hadoop Zookeeper Failover Controller
• cdh_hbase_common - common packages shared by all HBase nodes
• cdh_hbase_config - common configuration shared by all HBase nodes
• cdh_hbase_master - installs HBase-Master
• cdh_hbase_regionserver - installs HBase RegionServer
• cdh_hive_common - common packages shared by all Hive nodes
• cdh_hive_config - common configuration shared by all Hive nodes
• cdh_hive_metastore - installs Hive metastore (with PostgreSQL database)
• cdh_zookeeper_server - installs ZooKeeper Server

Facebook Presto Roles

• presto_common - downloads Presto to /usr/local/presto and prepares the node configuration
• presto_coordinator - installs Presto coordinator config
• presto_worker - installs Presto worker config

Configuration

Set the following variables using --extra-vars or editing group_vars/all:

Required:

• site_name - used as Hadoop nameservices and various directory names. Alphanumeric only.

Optional:

• Network interface: if you'd like to use a different IP address per host (eg. internal interface), change site.yml and change set_fact: ipv4_address=... to determine the correct IP address to use per host. If this fact is not set, ansible_default_ipv4.address will be used.
• Email notification: notify_email, postfix_domain, mandrill_username, mandrill_api_key
• roles/common: kernel_swappiness(0), nofile limits, ntp servers and rsyslog_polling_interval_secs(10)
• roles/2_aggregated_links: bond_mode (balance-alb) and mtu (9216)
• roles/cdh_hadoop_config: dfs_blocksize (268435456), max_xcievers (4096), heapsize (12278)

Adding hosts

Edit the hosts file and list hosts per group (see Inventory for more examples):

[datanodes]
hslave010
hslave[090:252]
hadoop-slave-[a:f].example.com

Make sure that the zookeepers and journalnodes groups contain at least 3 hosts and have an odd number of hosts.

Ganglia nodes

Since we're using unicast mode for Ganglia (which significantly reduces chatter), you may have to wait 60 seconds after node startup before it is seen/shows up in the web interface.

Installation

To run Ansible:

./site.sh

To e.g. just install ZooKeeper, add the zookeeper tag as argument (available tags: apache, bonding, configuration, elasticsearch, elasticsearch_curator, fluentd, ganglia, hadoop, hbase, hive, java, kibana, ntp, postfix, postgres, presto, rsyslog, tdagent, zookeeper):

./site.sh zookeeper

What else is installed?

• To improve performance, sysctl tuning
• link aggregation configures Link Aggregation if 2 interfaces are available
• htop, curl, checkinstall, heirloom-mailx, intel-microcode/amd64-microcode, net-tools, zip
• NTP configured with the Oxford University NTP service by default
• Postfix with Mandrill configuration
• unattended upgrades email to inform success/failure
• php5-cli, sysstat, hddtemp to report device metrics (reads/writes/temp) to Ganglia every 10 minutes
• LZO (Lempel–Ziv–Oberhumer) and Google Snappy 1.1.1 compression
• a fork of openjdk's FloatingDecimal to fix monitor contention when parsing doubles due to a static synchronized method
• Elasticsearch Curator, defaults to maximum 30 GB of data in Elasticsearch, via cron daily at 2:00AM
• Elasticsearch Marvel, monitor your Elasticsearch cluster's heartbeat
• SmokePing to keep track of network latency

URL's

After the installation, go here:

• Ganglia at monitor01/ganglia
• Kibana at monitor01/kibana/index.html#/dashboard/file/logstash.json
• Smokeping at monitor01/smokeping/smokeping.cgi
• hmaster01 at hmaster01:50070 - active namenode
• hmaster02 at hmaster02:50070 - standby namenode
• Presto at hmaster02:8081 - Presto coordinator

Performance testing

Instructions on how to test the performance of your CDH4 cluster.

• SSH into one of the machines.
• Change to the hdfs user: sudo su - hdfs
• Set HADOOP_MAPRED_HOME: export HADOOP_MAPRED_HOME=/usr/lib/hadoop-mapreduce
• cd /usr/lib/hadoop-mapreduce

TeraGen and TeraSort

• hadoop jar hadoop-mapreduce-examples.jar teragen -Dmapred.map.tasks=1000 10000000000 /tera/in to run TeraGen
• hadoop jar hadoop-mapreduce-examples.jar terasort /tera/in /tera/out to run TeraSort

DFSIO

• hadoop jar hadoop-mapreduce-client-jobclient-2.0.0-cdh4.6.0-tests.jar TestDFSIO -write

Bootstrapping

Paste your public SSH RSA key in bootstrap/ansible_rsa.pub and run bootstrap.sh to bootstrap the nodes specified in bootstrap/hosts. See bootstrap/bootstrap.yml for more information.

What about Pig, Flume, etc?

You can manually install additional components after running this playbook. Follow the official CDH4 Installation Guide.

Screenshots

License

Licensed under the Apache License, Version 2.0.

Copyright 2013-2014 Mathias Bogaert.