openstack-manuals/doc/admin-guide-cloud/source/database.rst

Database

The Database service provides database management features.

Introduction

The Database service provides scalable and reliable cloud provisioning functionality for both relational and non-relational database engines. Users can quickly and easily use database features without the burden of handling complex administrative tasks. Cloud users and database administrators can provision and manage multiple database instances as needed.

The Database service provides resource isolation at high performance levels, and automates complex administrative tasks such as deployment, configuration, patching, backups, restores, and monitoring.

Create a datastore

An administrative user can create datastores for a variety of databases.

This section assumes you do not yet have a MySQL datastore, and shows you how to create a MySQL datastore and populate it with a MySQL 5.5 datastore version.

To create a datastore

1. Create a trove image

   Create an image for the type of database you want to use, for example, MySQL, MongoDB, Cassandra.

   This image must have the trove guest agent installed, and it must have the trove-guestagent.conf file configured to connect to your OpenStack environment. To configure trove-guestagent.conf, add the following lines to trove-guestagent.conf on the guest instance you are using to build your image:

   rabbit_host = controller
   rabbit_password = RABBIT_PASS
   nova_proxy_admin_user = admin
   nova_proxy_admin_pass = ADMIN_PASS
   nova_proxy_admin_tenant_name = service
   trove_auth_url = http://controller:35357/v2.0

   This example assumes you have created a MySQL 5.5 image called mysql-5.5.qcow2.

2. Register image with Image service

   You need to register your guest image with the Image service.

   In this example, you use the glance image-create command to register a mysql-5.5.qcow2 image:

   $ glance image-create --name mysql-5.5 --disk-format qcow2 --container-format bare --is-public True < mysql-5.5.qcow2
   +------------------+--------------------------------------+
   | Property         | Value                                |
   +------------------+--------------------------------------+
   | checksum         | d41d8cd98f00b204e9800998ecf8427e     |
   | container_format | bare                                 |
   | created_at       | 2014-05-23T21:01:18                  |
   | deleted          | False                                |
   | deleted_at       | None                                 |
   | disk_format      | qcow2                                |
   | id               | bb75f870-0c33-4907-8467-1367f8cb15b6 |
   | is_public        | True                                 |
   | min_disk         | 0                                    |
   | min_ram          | 0                                    |
   | name             | mysql-5.5                            |
   | owner            | 1448da1223124bb291f5ae8e9af4270d     |
   | protected        | False                                |
   | size             | 0                                    |
   | status           | active                               |
   | updated_at       | 2014-05-23T21:01:22                  |
   | virtual_size     | None                                 |
   +------------------+--------------------------------------+

3. Create the datastore

   Create the datastore that will house the new image. To do this, use the trove-manage datastore_update command.

   This example uses the following arguments:

   Argument	Description	In this example:
   config file	The configuration file to use.	--config-file=/etc/trove/trove.conf
   name	Name you want to use for this datastore.	mysql
   default version	You can attach multiple versions/images to a datastore. For example, you might have a MySQL 5.5 version and a MySQL 5.6 version. You can designate one version as the default, which the system uses if a user does not explicitly request a specific version.	"" At this point, you do not yet have a default version, so pass in an empty string.

   Example:

   $ trove-manage --config-file=/etc/trove/trove.conf datastore_update mysql ""

4. Add a version to the new datastore

   Now that you have a MySQL datastore, you can add a version to it, using the trove-manage datastore_version_update command. The version indicates which guest image to use.

   This example uses the following arguments:

   Argument	Description	In this example:
   config file	The configuration file to use.	--config-file=/etc/trove/trove.conf
   datastore	The name of the datastore you just created via trove-manage datastore_update.	mysql
   version name	The name of the version you are adding to the datastore.	mysql-5.5
   datastore manager	Which datastore manager to use for this version. Typically, the datastore manager is identified by one of the following strings, depending on the database: mysql redis mongodb cassandra couchbase percona	mysql
   glance ID	The ID of the guest image you just added to the Identity service. You can get this ID by using the glance image-show IMAGE_NAME command.	bb75f870-0c33-4907-8467-1367f8cb15b6
   packages	If you want to put additional packages on each guest that you create with this datastore version, you can list the package names here.	"" In this example, the guest image already contains all the required packages, so leave this argument empty.
   active	Set this to either 1 or 0: 1 = active 0 = disabled	1

   Example:

   $ trove-manage --config-file=/etc/trove/trove.conf datastore_version_update mysql mysql-5.5 mysql GLANCE_ID "" 1

   Optional. Set your new version as the default version. To do this, use the trove-manage datastore_update command again, this time specifying the version you just created.

   $ trove-manage --config-file=/etc/trove/trove.conf datastore_update mysql mysql-5.5

5. Load validation rules for configuration groups

   Note

   Applies only to MySQL and Percona datastores

   • If you just created a MySQL or Percona datastore, then you need to load the appropriate validation rules, as described in this step.
   • If you just created a different datastore, skip this step.

   Background. You can manage database configuration tasks by using configuration groups. Configuration groups let you set configuration parameters, in bulk, on one or more databases.

   When you set up a configuration group using the trove configuration-create command, this command compares the configuration values you are setting against a list of valid configuration values that are stored in the validation-rules.json file.

   Operating System	Location of validation-rules.json	Notes
   Ubuntu 14.04	/usr/lib/python2.7/dist-packages/trove/templates/DATASTORE_NAME	DATASTORE_NAME is the name of either the MySQL datastore or the Percona datastore. This is typically either mysql or percona.
   RHEL 7, CentOS 7, Fedora 20, and Fedora 21	/usr/lib/python2.7/site-packages/trove/templates/DATASTORE_NAME	DATASTORE_NAME is the name of either the MySQL datastore or the Percona datastore. This is typically either mysql or percona.

   Therefore, as part of creating a datastore, you need to load the validation-rules.json file, using the trove-manage db_load_datastore_config_parameters command. This command takes the following arguments:

   • Datastore name
   • Datastore version
   • Full path to the validation-rules.json file

   This example loads the validation-rules.json file for a MySQL database on Ubuntu 14.04:

   $ trove-manage db_load_datastore_config_parameters mysql mysql-5.5 /usr/lib/python2.7/dist-packages/trove/templates/mysql/validation-rules.json

6. Validate datastore

   To validate your new datastore and version, start by listing the datastores on your system:

   $ trove datastore-list
   +--------------------------------------+--------------+
   |                  id                  |     name     |
   +--------------------------------------+--------------+
   | 10000000-0000-0000-0000-000000000001 | Legacy MySQL |
   | e5dc1da3-f080-4589-a4c2-eff7928f969a |    mysql     |
   +--------------------------------------+--------------+

   Take the ID of the MySQL datastore and pass it in with the datastore-version-list command:

   $ trove datastore-version-list DATASTORE_ID
   +--------------------------------------+-----------+
   |                  id                  |    name   |
   +--------------------------------------+-----------+
   | 36a6306b-efd8-4d83-9b75-8b30dd756381 | mysql-5.5 |
   +--------------------------------------+-----------+

Configure a cluster

An administrative user can configure various characteristics of a MongoDB cluster.

Query routers and config servers

Background. Each cluster includes at least one query router and one config server. Query routers and config servers count against your quota. When you delete a cluster, the system deletes the associated query router(s) and config server(s).

Configuration. By default, the system creates one query router and one config server per cluster. You can change this by editing the /etc/trove/trove.conf file. These settings are in the mongodb section of the file:

Setting	Valid values are:
num_config_servers_per_cluster	1 or 3
num_query_routers_per_cluster	1 or 3