ambari_modules

This ansible role host a set of modules aimed to ease some operation on Ambari.

• ambari_configs: Allow to read, define and modify configurations for Hadoop (or others) services managed by Ambari. Doc at this location

• ambari_host_services: Allow you to stop/start all services on a specific host. Typical use case is host rolling restart. Doc at this location

• ambari_service: Allow to stop/start/restart services managed by Ambari. Doc at this location

• ambari_uri: Usefully replace Ansible uri module for most if not all of Ambari API call. It will handle authentication, automatic cluster id setting and is able to wait completion for a deferred task. Doc at this location

Requirements

These modules need the python-requests package to be present on the remote node.

Example Playbook

# Modify Kafka configuration and restart services 

- hosts: sr1
  roles:
  - ambari_modules
  tasks:
  - name: Set kafka-broker configuration
    ambari_configs:
      ambari_url: "http://sr1.hdp16:8080"
      username: admin
      password: admin
      operation: set
      type: kafka-broker
      values:
        auto.create.topics.enable: "false"
        log.retention.hours: 220
        
  - name: Restart stale services
    ambari_service:
      ambari_url: "http://sr1.hdp16:8080"
      username: admin
      password: admin
      service: "_stale_"     # '_stale_' is a special token
      state: restarted

ambari_server parameter

If you look at the example above, you will see the first three parameters of each task are always the same. They define how the module acces to Ambari, not what ot does. In a larger playbook, this may be cumbersome.

To improve this, theses module accept a parameter ambari_server which must be a map hosting one or several of the following keys:

• ambari_url
• username
• password
• validate_certs
• ca_bundle_file

For example, the first task of the above example could be written:

  - name: Set kafka-broker configuration
    ambari_configs:
      ambari_server
        ambari_url: "http://sr1.hdp16:8080"
        username: admin
        password: admin
      operation: set
      type: kafka-broker
      values:
        auto.create.topics.enable: "false"
        log.retention.hours: 220

Not a very effective improvment! But we can now rewrite the full sample this way:

- hosts: sr1
  vars:
    ambariServer:
      ambari_url: "http://sr1.hdp16:8080"
      username: admin
      password: admin
  roles:
  - ambari_modules
  tasks:
  - name: Set kafka-broker configuration
    ambari_configs:
      ambari_server: "{{ambariServer}}"
      operation: set
      type: kafka-broker
      values:
        auto.create.topics.enable: "false"
        log.retention.hours: 220

  - name: Restart stale services
    ambari_service:
      ambari_server: "{{ambariServer}}"
      service: "_stale_"
      state: restarted

Obviously, if you have a playbook with a lot of Ambari action, this will improve readability.

License

GNU GPL

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