Ansible role ansible-role-XtraDB-Cluster

An Ansible role for setup a percon XtraDB Cluster. Specifically, the responsibilities of this role are to:

• install packages
• secure connections
• bootstrap the cluster

Requirements

No specific requirements

Role Variables

BASICS

MySQL part

For more info on the values, read the MariaDB Server System Variables documentation.

Adding databases

Databases are defined with a dict containing the fields name: (required), and init_script: (optional). The init script is a SQL file that is executed when the database is created to initialise tables and populate it with values.

xtradb_databases:
  - name: keystone
  - name: mydb
    init_script: files/init_mydb.sql

Adding users

Users are defined with a dict containing fields name:, password:, priv:, and, optionally, host:. The password is in plain text and priv: specifies the privileges for this user as described in the Ansible documentation.

An example:

xtradb_users:
  - name: keystone
    password: KEYSTONE_DBPASS
    priv: 'keystone.*:SUPER'

  - name: cdelgehier
    password: yolo
    priv: 'mydb.*:ALL'
    host: '192.168.1.%'

Dependencies

No dependencies.

Example Playbook

- hosts: db
  gather_facts: true
  become: true
  roles:
    - role: ansible-role-XtraDB-Cluster
      xtradb_cluster_name: "prod-customer"
      xtradb_sst_user: sstuser
      xtradb_sst_password: s3cr3t
      xtradb_root_password: yolo

      xtradb_nodes_group: "db"
      xtradb_bind_interface: eth0

- hosts: db
  gather_facts: true
  become: true
  roles:
    - role: ansible-role-XtraDB-Cluster
      xtradb_cluster_name: "prod-customer"
      xtradb_sst_user: sstuser
      xtradb_sst_password: s3cr3t
      xtradb_root_password: yolo

      xtradb_bind_address: "{{ ansible_default_ipv4.address }}"
      xtradb_wsrep_cluster_address: "gcomm://{{ groups['db'] | map('extract', hostvars, ['ansible_default_ipv4', 'address']) | join(',') }}"
      xtradb_master_node: "{{ hostvars[ groups['db'][0] ].ansible_default_ipv4.address }}"

- hosts: db
  gather_facts: true
  become: true
  roles:
    - role: ansible-role-XtraDB-Cluster
      xtradb_cluster_name: "prod-customer"
      xtradb_sst_password: s3cr3t
      xtradb_root_password: yolo
      xtradb_nodes_group: "db"
      xtradb_bind_interface: eth0

      xtradb_databases:
        - name: keystone
      xtradb_users:
        - name: keystone
          password: PASSWD
          priv: 'keystone.*:GRANT,ALL'

      xtradb_innodb_buffer_pool_instances: 8
      xtradb_innodb_buffer_pool_size: "384M"
      xtradb_innodb_file_format: "Barracuda"
      xtradb_innodb_file_format_check: "1"
      xtradb_innodb_file_per_table: "on"
      xtradb_innodb_flush_log_at_trx_commit: "1"
      xtradb_innodb_log_buffer_size: "16M"
      xtradb_innodb_log_file_size: "50M"
      xtradb_innodb_strict_mode: "on"
      xtradb_join_buffer_size: "128K"
      xtradb_log_warnings: "1"
      xtradb_long_query_time: "10"
      xtradb_max_allowed_packet: "16M"
      xtradb_max_connections: "505"
      xtradb_max_heap_table_size: "16M"
      xtradb_max_user_connections: "500"
      xtradb_query_cache_size: "0"   # disable
      xtradb_read_buffer_size: "128K"
      xtradb_read_rnd_buffer_size: "256k"
      xtradb_skip_name_resolve: "1"
      xtradb_slow_query_log: "1"
      xtradb_sort_buffer_size: "2M"
      xtradb_table_definition_cache: "1400"
      xtradb_table_open_cache: "2000"
      xtradb_table_open_cache_instances: "8"
      xtradb_tmp_table_size: "16M"

[db]
node1 ansible_host=192.168.1.173
node2 ansible_host=192.168.1.156
node3 ansible_host=192.168.1.154

Testing

There are two types of test environments available. One powered by Vagrant, another by Docker. The latter is suitable for running automated tests on Travis-CI. Test code is kept in separate orphan branches. For details of how to set up these test environments on your own machine, see the README files in the respective branches:

• Docker: docker-tests

Remove

To remove alltraces and start a new install

ansible  db -m shell -a 'rm -rf /var/lib/mysql /var/log/mysqld.log /etc/percona-xtradb-cluster.conf.d ; yum remove Percona* -y'

Contributing

Issues, feature requests, ideas are appreciated and can be posted in the Issues section.

Pull requests are also very welcome. The best way to submit a PR is by first creating a fork of this Github project, then creating a topic branch for the suggested change and pushing that branch to your own fork. Github can then easily create a PR based on that branch.

License

2-clause BSD license, see LICENSE.md

Contributors

• Cedric DELGEHIER (maintainer)