“services” section

You would want to have dedicated DB/messaging/memcached/etc for some of your services. Or you could have several backends and want to switch between them easily. This guide will describe how to make proper configuration for both cases.

All required configuration is located under services config group and can be propagated via ccp.yaml.

The following abstractions are being used all over the CCP:

• database
• rpc
• notifications

You should explicitly define backends for them before deployment. For example:

services:
  database:
    service_def: galera
  rpc:
    service_def: rabbitmq
  notifications:
    service_def: rabbitmq

Those services can be used in topology definition. You don’t have to define anything else. By default will be assumed that service has a name of service definition.

In the following example will be created dedicated databases for keystone and glance, dedicated memcached for keystone and horizon and those services will be connected through mapping section.

services:
  database:
    service_def: galera
  keystone-db:
    service_def: galera
  glance-db:
    service_def: galera

  keystone-memcached:
    service_def: memcached
  horizon-memcached:
    service_def: memcached

  rpc:
    service_def: rabbitmq
  notifications:
    service_def: rabbitmq

  keystone:
    service_def: keystone
    mapping:
      database: keystone-db
      memcached: keystone-memcached
  glance-api:
    service_def: glance-api
    mapping:
      database: glance-db
  glance-registry:
    service_def: glance-registry
    mapping:
      database: glance-db
  horizon:
    service_def: horizon
    mapping:
      memcached: horizon-memcached

Note

Each galera instance should have it’s own subset of nodes.