Set up session storage for the dashboard¶

Memcached¶

Memcached is a high-performance and distributed memory object caching system providing in-memory key-value store for small chunks of arbitrary data.

Requirements:

• Memcached service running and accessible.
• Python module python-memcached installed.

Enabled by:

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SESSION_ENGINE = 'django.contrib.sessions.backends.cache'
CACHES = {
  'default': {
    'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',
    'LOCATION': 'my_memcached_host:11211',
  }
}

Redis¶

Redis is an open source, BSD licensed, advanced key-value store. It is often referred to as a data structure server.

Requirements:

• Redis service running and accessible.
• Python modules redis and django-redis installed.

Enabled by:

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SESSION_ENGINE = 'django.contrib.sessions.backends.cache'
CACHES = {
    "default": {
        "BACKEND": "redis_cache.cache.RedisCache",
        "LOCATION": "127.0.0.1:6379:1",
        "OPTIONS": {
            "CLIENT_CLASS": "redis_cache.client.DefaultClient",
        }
    }
}

Initialize and configure the database¶

Database-backed sessions are scalable, persistent, and can be made high-concurrency and highly-available.

However, database-backed sessions are one of the slower session storages and incur a high overhead under heavy usage. Proper configuration of your database deployment can also be a substantial undertaking and is far beyond the scope of this documentation.

1. Start the mysql command-line client:

   $ mysql -u root -p
   

2. Enter the MySQL root user’s password when prompted.

3. To configure the MySQL database, create the dash database:

   mysql> CREATE DATABASE dash;
   

4. Create a MySQL user for the newly created dash database that has full control of the database. Replace DASH_DBPASS with a password for the new user:

   mysql> GRANT ALL PRIVILEGES ON dash.* TO 'dash'@'%' IDENTIFIED BY 'DASH_DBPASS';
   mysql> GRANT ALL PRIVILEGES ON dash.* TO 'dash'@'localhost' IDENTIFIED BY 'DASH_DBPASS';
   

5. Enter quit at the mysql> prompt to exit MySQL.

6. In the local_settings file (on Fedora/RHEL/CentOS: /etc/openstack-dashboard/local_settings, on Ubuntu/Debian: /etc/openstack-dashboard/local_settings.py, and on openSUSE: /srv/www/openstack-dashboard/openstack_dashboard/local/local_settings.py), change these options:

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   SESSION_ENGINE = 'django.contrib.sessions.backends.db' DATABASES = { 'default': { # Database configuration here 'ENGINE': 'django.db.backends.mysql', 'NAME': 'dash', 'USER': 'dash', 'PASSWORD': 'DASH_DBPASS', 'HOST': 'localhost', 'default-character-set': 'utf8' } }

7. After configuring the local_settings file as shown, you can run the manage.py syncdb command to populate this newly created database:

   # /usr/share/openstack-dashboard/manage.py syncdb
   

   Note on openSUSE the path is /srv/www/openstack-dashboard/manage.py.

8. The following output is returned:

   Installing custom SQL ...
   Installing indexes ...
   DEBUG:django.db.backends:(0.008) CREATE INDEX `django_session_c25c2c28` ON `django_session` (`expire_date`);; args=()
   No fixtures found.
   

9. To avoid a warning when you restart Apache on Ubuntu, create a blackhole directory in the dashboard directory, as follows:

   # mkdir -p /var/lib/dash/.blackhole
   

10. Restart and refresh Apache:

    On Ubuntu:

    # /etc/init.d/apache2 restart
    

    On Fedora/RHEL/CentOS:

    # service httpd restart
    # service apache2 restart
    

    On openSUSE:

    # systemctl restart apache2.service
    

11. On Ubuntu, restart the nova-api service to ensure that the API server can connect to the dashboard without error:

    # service nova-api restart