hadoop

Formula to set up and configure hadoop components

Note

See the full Salt Formulas installation and usage instructions.

Available states

hadoop

Downloads the hadoop tarball from the hadoop:source_url, installs the package, creates the hadoop group for all other components to share.

hadoop.hdfs

Installs the hdfs service configuration and starts the hdfs services. Which services hadoop ends up running on a given host depends on the roles defined via salt grains:

• hadoop_master will run the hadoop-namenode and hadoop-secondarynamenode services
• hadoop_slave will run the hadoop-datanode service

roles:
  - hadoop_slave

hadoop.mapred

Installs the mapreduce service scripts and configuration, adds directories. Which services end up running on a given host will again depend on the role(s) assigned via grains:

• hadoop_master will run the hadoop-jobtracker service
• hadoop_slave will run the hadoop-tasktracker service

hadoop.snappy

Install snappy and snappy-devel system packages, adds a jar and shared lib compiled off of https://code.google.com/p/hadoop-snappy and also puts symlinks to the snappy libs in place, thus providing compression with snappy to the ecosystem.

hadoop.yarn

Installs the yarn daemon scripts and configuration (if a hadoop 2.2+ version was installed), adds directories. Which services end up running on a given host will again depend on the role(s) assigned via grains:

• hadoop_master will run the hadoop-resourcemanager service
• hadoop_slave will run the hadoop-nodemanager service

hadoop.hdfs.uninstall ---------------

Stops the hdfs services and uninstalls the hdfs service configuration. Removes hdfs data from local disks.

hadoop.mapred.uninstall ---------------

Uninstalls the mapreduce service scripts and configuration. Removes mapred data from local disks.

hadoop.yarn.uninstall ---------------

Uninstalls the yarn daemon scripts and configuration. Removes yarn data from local disks.

hadoop.uninstall ---------------

Uninstalls all Hadoop services and configurations.

Formula Dependencies

• hostsfile
• sun-java

Salt Minion Configuration

As mentioned above, all installation and configuration is assinged via roles. Mounted disks (or just directories) can be configured for use with hdfs and mapreduce via grains.

Example /etc/salt/grains for a datanode: :

hdfs_data_disks:
  - /data1
  - /data2
  - /data3
  - /data4

mapred_data_disks:
  - /data1
  - /data2
  - /data3
  - /data4

yarn_data_disks:
  - /data1
  - /data2
  - /data3
  - /data4

roles:
  - hadoop_slave

For the namenode address to be dynamically configured it is necessary to setup salt mine like below /etc/salt/minion.d/mine_functions.conf:

mine_functions:
  network.interfaces: []
  network.ip_addrs: []
  grains.items: []

One thing to keep in mind here is that the implementation currently relies on the minion_id of all nodes to match their FQDN (which is the default) and working name resolution.

Hadoop configuration

The hadoop formula exposes the general (cluster-independent) part of the main configuration files (core-site.xml, hdfs-site.sml, mapred-site.xml) as pillar keys.

Example: :

hadoop:
  config:
    tmp_dir: /var/lib/hadoop/tmp
    directory: /etc/hadoop/conf
    core-site:
      io.native.lib.available:
        value: true
      io.file.buffer.size:
        value: 65536
      fs.trash.interval:
        value: 60

Where the core-site part will appear in core-site.xml as: :

<property>
    <name>io.native.lib.available</name>
    <value>True</value>
</property>

<property>
    <name>fs.trash.interval</name>
    <value>60</value>
</property>

<property>
    <name>io.file.buffer.size</name>
    <value>65536</value>
</property>

Please note that host- and cluster-specific values are not exposed - the formula controls these (think: fs.default.name)

Custom Hadoop distribution settings

The formula includes all data to allow referencing a specific distribution release by simply using the version key:

Example: :

hadoop:
  version: hdp-2.6.0

This example will make the formula use the latest (maintained) version of HDP-2.2 (which happens to be Hadoop 2.6.0). At the time this documentation is written this is more specifically 2.6.0.2.2.6.0-2800, an update release that will soon change and with some likelyhood be what you need.

If for whatever reason that is not the case (because for example you need to provision HDP 2.6.0.2.2.4.2-2) then you need to provide the full data structure in the versions hash that is normally part of the formula.

Example: :

hadoop:
  version: hdp-2.6.0-update2242
  versions:
    hdp-2.6.0-update2242:
      version: 2.6.0.2.2.4.2-2
      version_name: hadoop-2.6.0.2.2.4.2-2
      source_url: http://public-repo-1.hortonworks.com/HDP/centos6/2.x/updates/2.2.4.2/tars/hadoop-2.6.0.2.2.4.2-2.tar.gz
      major_version: '2'
    hdp-2.6.0-GA:
      version: 2.6.0.2.2.0.0-2041
      version_name: hadoop-2.6.0.2.2.0.0-2041
      source_url: http://public-repo-1.hortonworks.com/HDP/centos6/2.x/GA/2.2.0.0/tars/hadoop-2.6.0.2.2.0.0-2041.tar.gz
      major_version: '2'

This would end up provisioning the earlier update version and additionally give you a way to install the GA version - just by changing the hadoop.version attribute to hdp-2.6.0-GA.