ansible-role-cassandra

Ansible role to install and configure Apache Cassandra.

Requirements

OS Family Identification

The Ansible playbook must gather enough facts to have the ansible_os_family variable to be set.

Python Modules

On Debian systems that set cassandra_configure_apache_repo to True please note that the apt_repository module is used. Therefore the below requirements are needed on the host that executes this module.

python-apt (python 2)
python3-apt (python 3)

Role Variables

cassandra_cms_heap_new_size_mb: A custom fact that returns a value (MB) that might be suitable to set the HEAP_NEWSIZE when using the Concurrent Mark Sweep (CMS) Collector. See Tuning Java resources for more details. Requires the ansible_memtotal_mb and ansible_processor_vcpus facts to be set.
cassandra_cms_max_heapsize_mb: A custom fact that returns a value (MB) that might be suitable to set the MAX_HEAP_SIZE when using the Concurrent Mark Sweep (CMS) Collector. See Tuning Java resources for more details. Requires the ansible_memtotal_mb fact to be set.
cassandra_configuration (default: none): The configuration for Cassandra. See the example play book below.
cassandra_configuration_file (default: /etc/cassandra/default.conf/cassandra.yaml on RedHat and /etc/cassandra/cassandra.yaml on Debian): The location of the Cassandra configuration file.
cassandra_configuration_templ (default: cassandra.yaml.j2): Name of the template file for Cassandra configuration.
cassandra_configure_apache_repo (default: False): Whether to configure the Apache Cassandra repository.

SEE ALSO: cassandra_repo_apache_release.
cassandra_directories: If defined, this will create directories after the package has been installed (therefore when the cassandra user is available) but before Cassandra is configured. See the example playbook for more details.
cassandra_heap_new_size_mb: A custom fact that returns a value (MB) that might be suitable to set the HEAP_NEWSIZE. See Tuning Java resources for more details. Requires the ansible_memtotal_mb and ansible_processor_vcpus facts to be set.
cassandra_max_heapsize_mb: A custom fact that returns a value (MB) that might be suitable to set the MAX_HEAP_SIZE. See Tuning Java resources for more details. Requires the ansible_memtotal_mb fact to be set.
cassandra_package (default: cassandra): The name of the package to be installed to provide Cassandra.
cassandra_repo_apache_release (default: None): The name of the release series (can be one of 311x, 30x, 22x, or 21x). This must be set if cassandra_configure_apache_repo is set to True.
cassandra_service_enabled (default: yes): Should the cassandra service be enabled (can be yes or no).
cassandra_service_restart (default: True): If set to true, changes to the Cassandra configuration file or the data directories will ensure that Cassandra service is refreshed after the changes. Setting this flag to false will disable this behaviour, therefore allowing the changes to be made but allow the user to control when the service is restarted.
cassandra_systemd_enabled (default: False): Should the Cassandra service by enabled via systemd if set to True then a unit file will be placed in cassandra_systemd_path created from template cassandra_systemd_template.
cassandra_systemd_path (default: /usr/lib/systemd/system/cassandra.service): The path to a unit file for Cassandra. This variable is ignored if cassandra_systemd_enabled is False.
cassandra_systemd_template (default: "systemd/system/{{ ansible_facts.distribution }}/{{ ansible_facts.distribution_major_version }}/cassandra.service.j2": The path for a template from which to create unit file for Cassandra. This variable is ignored if cassandra_systemd_enabled is False.
cassandra_task_delay (default: 10): Ansible tasks that rely on network connectivity (i.e. apt, apt_key, apt_repository, package and yum) may be affected by high latency so those tasks are configured to retry. This parameter is how long to wait between attempts. See also cassandra_task_retries.
cassandra_task_retries (default: 5): Ansible tasks that rely on network connectivity (i.e. apt, apt_key, apt_repository, package and yum) may be affected by high latency so those tasks are configured to retry. This parameter is how many attempts should be made. See also cassandra_task_delay.

Example Playbook

This playbook should be enough to configure Cassandra with a very basic configuration:

---
- name: Example Playbook for the locp.cassandra Role

  hosts: cassandra

  remote_user: root

  vars:
    cassandra_configuration:
      authenticator: PasswordAuthenticator
      cluster_name: MyCassandraCluster
      commitlog_directory: /data/cassandra/commitlog
      commitlog_sync: periodic
      commitlog_sync_period_in_ms: 10000
      data_file_directories:
        - /data/cassandra/data
      endpoint_snitch: GossipingPropertyFileSnitch
      hints_directory: "/data/cassandra/hints"
      listen_address: "{{ ansible_default_ipv4.address }}"
      partitioner: org.apache.cassandra.dht.Murmur3Partitioner
      saved_caches_directory: /data/cassandra/saved_caches
      seed_provider:
        - class_name: "org.apache.cassandra.locator.SimpleSeedProvider"
          parameters:
            - seeds: "{{ ansible_default_ipv4.address }}"
      start_native_transport: true
    cassandra_configure_apache_repo: true
    cassandra_dc: DC1
    # Create an alternative directories structure for the Cassandra data.
    # In this example, the will be a directory called /data owned by root
    # with rwxr-xr-x permissions.  It will have a series of sub-directories
    # all of which will be defaulted to being owned by the cassandra user
    # with rwx------ permissions.
    cassandra_directories:
      root:
        group: root
        mode: "0755"
        owner: root
        paths:
          - /data
      data:
        paths:
          - /data/cassandra
          - /data/cassandra/commitlog
          - /data/cassandra/data
          - /data/cassandra/hints
          - /data/cassandra/saved_caches
    cassandra_rack: RACK1
    cassandra_repo_apache_release: 311x

  pre_tasks:
    - name: Enable Systemd
      set_fact:
        cassandra_systemd_enabled: True
      when: ansible_os_family == 'RedHat'

    - name: Disable Cassandra Restart
      set_fact:
        cassandra_service_restart: False
      when:
        - ansible_os_family == 'Debian'
        - ansible_distribution_major_version == '10'

  roles:
    - role: locp.cassandra

License

GPLv3

Author Information

Developed by the League of Crafty Programmers Ltd.

To raise issues or make contributions, please go to https://github.com/locp/ansible-role-cassandra/issues

sdarshanam / ansible-role-cassandra