# Standalone PostgreSQL using Omnibus GitLab **(CORE ONLY)**

If you wish to have your database service hosted separately from your GitLab
application server(s), you can do this using the PostgreSQL binaries packaged
together with Omnibus GitLab. This is recommended as part of our
[reference architecture for up to 2,000 users](../reference_architectures/2k_users.md).

## Setting it up

1. SSH into the PostgreSQL server.
1. [Download/install](https://about.gitlab.com/install/) the Omnibus GitLab
   package you want using **steps 1 and 2** from the GitLab downloads page.
   - Do not complete any other steps on the download page.
1. Generate a password hash for PostgreSQL. This assumes you will use the default
   username of `gitlab` (recommended). The command will request a password
   and confirmation. Use the value that is output by this command in the next
   step as the value of `POSTGRESQL_PASSWORD_HASH`.

   ```shell
   sudo gitlab-ctl pg-password-md5 gitlab
   ```

1. Edit `/etc/gitlab/gitlab.rb` and add the contents below, updating placeholder
   values appropriately.

   - `POSTGRESQL_PASSWORD_HASH` - The value output from the previous step
   - `APPLICATION_SERVER_IP_BLOCKS` - A space delimited list of IP subnets or IP
     addresses of the GitLab application servers that will connect to the
     database. Example: `%w(123.123.123.123/32 123.123.123.234/32)`

   ```ruby
   # Disable all components except PostgreSQL
   roles ['postgres_role']
   repmgr['enable'] = false
   consul['enable'] = false
   prometheus['enable'] = false
   alertmanager['enable'] = false
   pgbouncer_exporter['enable'] = false
   redis_exporter['enable'] = false
   gitlab_exporter['enable'] = false

   postgresql['listen_address'] = '0.0.0.0'
   postgresql['port'] = 5432

   # Replace POSTGRESQL_PASSWORD_HASH with a generated md5 value
   postgresql['sql_user_password'] = 'POSTGRESQL_PASSWORD_HASH'

   # Replace XXX.XXX.XXX.XXX/YY with Network Address
   # ????
   postgresql['trust_auth_cidr_addresses'] = %w(APPLICATION_SERVER_IP_BLOCKS)

   # Disable automatic database migrations
   gitlab_rails['auto_migrate'] = false
   ```

   NOTE: **Note:** The role `postgres_role` was introduced with GitLab 10.3

1. [Reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect.
1. Note the PostgreSQL node's IP address or hostname, port, and
   plain text password. These will be necessary when configuring the GitLab
   application servers later.
1. [Enable monitoring](replication_and_failover.md#enable-monitoring)

Advanced configuration options are supported and can be added if
needed.