Create and access a database instance

Assume that you have installed the Database service and populated your data store with images for the type and versions of databases that you want, and that you can create and access a database instance.

This example shows you how to create and access a MySQL 5.7 database.

Create and access a database instance

1. Determine which flavor to use for your database

   When you create a database instance, you must specify a nova flavor. The flavor indicates various characteristics of the instance, such as RAM and root volume size. You will need to create or obtain new nova flavors that work for databases.

   The first step is to list flavors by using the openstack flavor list command.

   $ openstack flavor list
   

   Now take a look at the minimum requirements for various database instances:

   Database	RAM (MB)	Disk (GB)	VCPUs
   MySQL	512	5	1
   Cassandra	2048	5	1
   MongoDB	1024	5	1
   Redis	512	5	1

   • If you have a custom flavor that meets the needs of the database that you want to create, proceed to Step 2 and use that flavor.

   • If your environment does not have a suitable flavor, an administrative user must create a custom flavor by using the openstack flavor create command.

   MySQL example. This example creates a flavor that you can use with a MySQL database. This example has the following attributes:

   • Flavor name: mysql_minimum

   • Flavor ID: You must use an ID that is not already in use. In this example, IDs 1 through 5 are in use, so use ID 6.

   • RAM: 512

   • Root volume size in GB: 5

   • Virtual CPUs: 1

   $ openstack flavor create mysql-minimum --id 6 --ram 512 --disk 5 --vcpus 1
   +----------------------------+---------------+
   | Field                      | Value         |
   +----------------------------+---------------+
   | OS-FLV-DISABLED:disabled   | False         |
   | OS-FLV-EXT-DATA:ephemeral  | 0             |
   | disk                       | 5             |
   | id                         | 6             |
   | name                       | mysql-minimum |
   | os-flavor-access:is_public | True          |
   | properties                 |               |
   | ram                        | 512           |
   | rxtx_factor                | 1.0           |
   | swap                       |               |
   | vcpus                      | 1             |
   +----------------------------+---------------+
   

2. Create a database instance

   This example creates a database instance with the following parameters:

   • Name of the instance: mysql_instance_1

   • Database flavor: 6

   • A volume size of 5 (5 GB)

   • A database named test

   • The database is based on the mysql data store and the 5.7 datastore version

   • The userA user with the password password.

   • A Neutron network 8799cf10-01ef-40e2-b04e-06da7cfa5668 to allocate the database IP address (for internal access).

   • Expose the instance to the public via --is-public (for external access). Ignore this parameter if you don’t want to expose database service to the public internet.

   • Only the IP addresses coming from 202.37.199.1/24 or 10.1.0.1/24 are allowed to access the database service.

   $ openstack database instance create mysql_instance_1 \
       --flavor 6 \
       --size 5 \
       --nic net-id=8799cf10-01ef-40e2-b04e-06da7cfa5668 \
       --databases test --users userA:password \
       --datastore mysql --datastore-version 5.7 \
       --is-public \
       --allowed-cidr 10.1.0.1/24 \
       --allowed-cidr 202.37.199.1/24
   +-------------------+--------------------------------------+
   | Field             | Value                                |
   +-------------------+--------------------------------------+
   | created           | 2019-09-11T09:19:18                  |
   | datastore         | mysql                                |
   | datastore_version | 5.7                                  |
   | flavor            | 6                                    |
   | id                | 4bca2f27-f986-419e-ab4a-df1db399d590 |
   | name              | mysql_instance_1                     |
   | region            | RegionOne                            |
   | status            | BUILD                                |
   | updated           | 2019-09-11T09:19:18                  |
   | volume            | 5                                    |
   +-------------------+--------------------------------------+
   

3. Get the IP address of the database instance

   Both internal and external IP addresses can be shown by running:

   $ openstack database instance show 4bca2f27-f986-419e-ab4a-df1db399d590
   +-------------------+--------------------------------------+
   | Field             | Value                                |
   +-------------------+--------------------------------------+
   | created           | 2019-09-11T07:14:37                  |
   | datastore         | mysql                                |
   | datastore_version | 5.7                                  |
   | flavor            | 6                                    |
   | id                | 4bca2f27-f986-419e-ab4a-df1db399d590 |
   | ip                | 10.1.0.14, 172.24.5.15               |
   | name              | mysql_instance_1                     |
   | region            | RegionOne                            |
   | status            | ACTIVE                               |
   | updated           | 2019-09-11T07:14:47                  |
   | volume            | 5                                    |
   | volume_used       | 0.12                                 |
   +-------------------+--------------------------------------+
   

4. Access the new database

   You can now access the new database you just created by using typical database access commands. In this MySQL example, replace IP_ADDRESS with either 10.1.0.14 or 172.24.5.15 according to where the command is running. Make sure your IP address is in the allowed CIDRs specified in the above command.

   $ mysql -h IP_ADDRESS -uuserA -ppassword