Skip to content

Latest commit

 

History

History
603 lines (448 loc) · 24.8 KB

database.md

File metadata and controls

603 lines (448 loc) · 24.8 KB

Database settings

Note: Omnibus GitLab has a bundled PostgreSQL server and PostgreSQL is the preferred database for GitLab.

GitLab supports the following database management systems:

  • PostgreSQL
  • MySQL/MariaDB

Thus you have three options for database servers to use with Omnibus GitLab:

If you are planning to use MySQL/MariaDB, make sure to read the introductory paragraph before proceeding, as it contains some useful information.

Configuring SSL

Omnibus automatically enables SSL on the PostgreSQL server, but it will accept both encrypted and unencrypted connections by default. Enforcing SSL requires using the hostssl configuration in pg_hba.conf. See https://www.postgresql.org/docs/9.6/static/auth-pg-hba-conf.html for more details.

SSL support depends on a number of files:

  1. The public SSL certificate for the database (server.crt).
  2. The corresponding private key for the SSL certificate (server.key).
  3. A root certificate bundle that validates the server's certificate (root.crt). By default, Omnibus GitLab will use the embedded certificate bundle in /opt/gitlab/embedded/ssl/certs/cacert.pem. This is not required for self-signed certificates

A self-signed certificate and private key will be automatically generated for use. If you'd prefer to use a CA-signed certificate, follow the steps below.

Note that the location of these files can be configurable, but the private key MUST be readable by the gitlab-psql user. Omnibus will automatically manage the permissions of the files for you, but you must ensure that the gitlab-psql can access the directory the files are placed in, if the paths are customized.

For more details, see the PostgreSQL documentation.

Note that server.crt and server.key may be different from the default SSL certificates used to access GitLab. For example, suppose the external hostname of your database is database.example.com, and your external GitLab hostname is gitlab.example.com. You will either need a wildcard certificate for *.example.com or two different SSL certificates.

With these files in hand, enable SSL:

  1. Edit /etc/gitlab/gitlab.rb:

    postgresql['ssl_cert_file'] = '/custom/path/to/server.crt'
postgresql['ssl_key_file'] = '/custom/path/to/server.key'
postgresql['ssl_ca_file'] = '/custom/path/to/bundle.pem'
postgresql['internal_certificate'] = "-----BEGIN CERTIFICATE-----
...base64-encoded certificate...
-----END CERTIFICATE-----
"
postgresql['internal_key'] = "-----BEGIN RSA PRIVATE KEY-----
...base64-encoded private key...
-----END RSA PRIVATE KEY-----
"

    Relative paths will be rooted from the PostgreSQL data directory (/var/opt/gitlab/postgresql/data by default).

  2. Reconfigure GitLab to apply the configuration changes.

  3. Restart PostgreSQL for the changes to take effect:

    gitlab-ctl restart postgresql

    If PostgreSQL fails to start, check the logs (e.g. /var/log/gitlab/postgresql/current) for more details.

Disabling SSL

  1. Add the following to /etc/gitlab/gitlab.rb:
postgresql['ssl'] = 'off'

  1. Reconfigure GitLab to apply the configuration changes.

  2. Restart PostgreSQL for the changes to take effect:

    gitlab-ctl restart postgresql

    If PostgreSQL fails to start, check the logs (e.g. /var/log/gitlab/postgresql/current) for more details.

Verifying that SSL is being used

To check whether SSL is being used by clients, you can run:

gitlab-rails dbconsole

At startup, you should see a banner as the following:

psql (9.6.5)
SSL connection (protocol: TLSv1.2, cipher: ECDHE-RSA-AES256-GCM-SHA384, bits: 256, compression: on)
Type "help" for help.

To check whether clients are using SSL, you can issue this SQL query:

SELECT * FROM pg_stat_ssl;

For example:

gitlabhq_production=> SELECT * FROM pg_stat_ssl;
  pid  | ssl | version |           cipher            | bits | compression | clientdn
-------+-----+---------+-----------------------------+------+-------------+----------
 47506 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47509 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47510 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47527 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47528 | f   |         |                             |      |             |
 47537 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47560 | f   |         |                             |      |             |
 47561 | f   |         |                             |      |             |
 47563 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47564 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47565 | f   |         |                             |      |             |
 47569 | f   |         |                             |      |             |
 47570 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47573 | f   |         |                             |      |             |
 47585 | f   |         |                             |      |             |
 47586 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47618 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 47628 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
 55812 | t   | TLSv1.2 | ECDHE-RSA-AES256-GCM-SHA384 |  256 | t           |
(19 rows)

Rows that have t listed under the ssl column are enabled.

Enabling PostgreSQL WAL (Write Ahead Log) Archiving

By default WAL archiving of the packaged PostgreSQL is not enabled. Please consider the following when seeking to enable WAL archiving:

  • The WAL level needs to be 'replica' or higher (9.6+ options are minimal, replica, or logical)
  • Increasing the WAL level will increase the amount of storage consumed in regular operations

To enable WAL Archiving:

  1. Edit /etc/gitlab/gitlab.rb:

    # Replication settings
postgresql['sql_replication_user'] = "gitlab_replicator"
postgresql['wal_level'] = "replica"
    ...
    ...
# Backup/Archive settings
postgresql['archive_mode'] = "on"
postgresql['archive_command'] = "/your/wal/archiver/here"
postgresql['archive_timeout'] = "60"

  2. Reconfigure GitLab for the changes to take effect. This will result in a database restart.

Using a non-packaged PostgreSQL database management server

By default, GitLab is configured to use the PostgreSQL server that is included in Omnibus GitLab. You can also reconfigure it to use an external instance of PostgreSQL.

WARNING If you are using non-packaged PostgreSQL server, you need to make sure that PostgreSQL is set up according to the database requirements document.

  1. Edit /etc/gitlab/gitlab.rb:

    # Disable the built-in Postgres
postgresql['enable'] = false

# Fill in the connection details for database.yml
gitlab_rails['db_adapter'] = 'postgresql'
gitlab_rails['db_encoding'] = 'utf8'
gitlab_rails['db_host'] = '127.0.0.1'
gitlab_rails['db_port'] = 5432
gitlab_rails['db_username'] = 'USERNAME'
gitlab_rails['db_password'] = 'PASSWORD'

    Don't forget to remove the # comment characters at the beginning of these lines.

    Note:

    • /etc/gitlab/gitlab.rb should have file permissions 0600 because it contains plain-text passwords.

    • Postgresql allows to listen on multiple addresses

      If you use multiple addresses in gitlab_rails['db_host'], comma-separated, the first address in the list will be used for connection.

  2. Reconfigure GitLab for the changes to take effect.

  3. Seed the database.

Backup and restore a non-packaged PostgreSQL database

When using the rake backup create and restore task, GitLab will attempt to use the packaged pg_dump command to create a database backup file and the packaged psql command to restore a backup. This will only work if they are the correct versions. Check the versions of the packaged pg_dump and psql:

/opt/gitlab/embedded/bin/pg_dump --version
/opt/gitlab/embedded/bin/psql --version

If these versions are different from your non-packaged external PostgreSQL, you will need to install tools that match your database version and then follow the steps below. There are multiple ways to install PostgreSQL client tools. See https://www.postgresql.org/download/ for options.

Once the correct psql and pg_dump tools are available on your system, follow these steps, using the correct path to the location you installed the new tools:

  1. Add symbolic links to the non-packaged versions:

    ln -s /path/to/new/pg_dump /path/to/new/psql /opt/gitlab/bin/

  2. Check the versions:

    /opt/gitlab/bin/pg_dump --version
/opt/gitlab/bin/psql --version

    They should now be the same as your non-packaged external PostgreSQL.

After this is done, ensure that the backup and restore tasks are using the correct executables by running both the backup and restore tasks.

Configure packaged PostreSQL server to listen on TCP/IP

The packaged PostgreSQL server can be configured to listen for TCP/IP connections, with the caveat that some non-critical scripts expect UNIX sockets and may misbehave.

In order to configure the use of TCP/IP for the database service, changes will need to be made to both postgresql and gitlab_rails sections of gitlab.rb.

Configure postgresql block

The following settings are affected in the postgresql block:

  • listen_address controls the address on which PostgreSQL will listen.
  • port controls the port on which PostgreSQL will listen, and must be set if listen_address is.
  • md5_auth_cidr_addresses is a list of CIDR address blocks which are allowed to connect to the server, after authentication via password.
  • trust_auth_cidr_addresses is a list of CIDR address blocks which are allowed to connect to the server, without authentication of any kind. Be very careful with this setting. It is suggest that this be limited to the loopback address of 127.0.0.1/24 or even 127.0.0.1/32.
  • sql_user controls the expected username for MD5 authentication. This defaults to gitlab, and is not a required setting.
  • sql_user_password sets the password that PostgrSQL will accept for MD5 authentication. Replace securesqlpassword in the example below with an acceptable password.
postgresql['listen_address'] = '0.0.0.0'
postgresql['port'] = 5432
postgresql['md5_auth_cidr_addresses'] = %w()
postgresql['trust_auth_cidr_addresses'] = %w(127.0.0.1/24)
postgresql['sql_user'] = "gitlab"
postgresql['sql_user_password'] = Digest::MD5.hexdigest "securesqlpassword" << postgresql['sql_user']

Any client or GitLab service which will connect over the network will need to provide the values of sql_user for the username, and password provided to the configuration when connecting to the PostgreSQL server. They must also be within the network block provided to md5_auth_cidr_addresses

Configure gitlab-rails block

To configure the gitlab-rails application to connect to the PostgreSQL database over the network, several settings must be configured.

  • db_host needs to be set to the IP address of the database sever. If this is on the same instance as the PostgrSQL service, this can be 127.0.0.1 and will not require password authentication.
  • db_port sets the port on the PostgreSQL server to connect to, and must be set if db_host is set.
  • db_username configures the username with which to connect to PostgreSQL. This defaults to gitlab.
  • db_password must be provided if connecting to PostgreSQL over TCP/IP, and from an instance in the postgresql['md5_auth_cidr_addresses'] block from settings above. This is not required if you are connecting to 127.0.0.1 and have configured postgresql['trust_auth_cidr_addresses'] to include it.
gitlab_rails['db_host'] = '127.0.0.1'
gitlab_rails['db_port'] = 5432
gitlab_rails['db_username'] = "gitlab"
gitlab_rails['db_password'] = "securesqlpassword"

Apply and restart services

After making the changes above, an administrator should run gitlab-ctl reconfigure. If you experience any issues in regards to the service not listening on TCP, try directly restarting the service with gitlab-ctl restart postgresql

Note: Some included scripts of the Omnibus package, such as gitlab-psql expect the connections to Postgres to be handled over the UNIX socket, and may not function properly. You can enable TCP/IP without disabling UNIX sockets.

Store PostgreSQL data in a different directory

By default, everything is stored under /var/opt/gitlab/postgresql, controlled by the postgresql['dir'] attribute.

This consists of

  1. The database socket will be /var/opt/gitlab/postgresql/.s.PGSQL.5432. This is controlled by postgresql['unix_socket_directory']
  2. The gitlab-psql system user will have its HOME directory set to this. This is controlled by postgresql['home']
  3. The actual data will be stored in /var/opt/gitlab/postgresql/data

To change the location of the PostgreSQL data

Warning: If you have an existing database, you need to move the data to the new location first

Warning: This is an intrusive operation. It cannot be done without downtime on an existing installation

  1. Stop GitLab if this is an existing installation: gitlab-ctl stop
  2. Update postgresql['dir'] to the desired location.
  3. Run gitlab-ctl reconfigure
  4. Start GitLab gitlab-ctl start

Using a MySQL database management server (Enterprise Edition only)

Note: Using MySQL with the Omnibus GitLab package is considered deprecated. Although GitLab Enterprise Edition will still work when MySQL is used, there will be some limitations as outlined in the database requirements document.

MySQL in Omnibus GitLab package is only supported in GitLab Enterprise Edition Starter and Premium. The MySQL server itself is not shipped with Omnibus, you will have to install it on your own or use an existing one. Omnibus ships only the MySQL client.

Make sure that GitLab's MySQL database collation is UTF-8, otherwise you could hit collation issues. See Set MySQL collation to UTF-8 to fix any relevant errors.

The following guide assumes that you want to use MySQL or MariaDB and are using the GitLab Enterprise Edition packages.

Important note: If you are connecting Omnibus GitLab to an existing GitLab database you should create a backup before attempting this procedure.

  1. First, set up your database server according to the upstream GitLab instructions. If you want to keep using an existing GitLab database you can skip this step.

  2. Next, add the following settings to /etc/gitlab/gitlab.rb:

    # Disable the built-in Postgres
postgresql['enable'] = false

# Fill in the values for database.yml
gitlab_rails['db_adapter'] = 'mysql2'
gitlab_rails['db_encoding'] = 'utf8'
gitlab_rails['db_host'] = '127.0.0.1'
gitlab_rails['db_port'] = 3306
gitlab_rails['db_username'] = 'USERNAME'
gitlab_rails['db_password'] = 'PASSWORD'

    db_adapter and db_encoding should be like the example above. Change all other settings according to your MySQL setup.

    Note: /etc/gitlab/gitlab.rb should have file permissions 0600 because it contains plain-text passwords.

  3. Reconfigure GitLab for the changes to take effect.

  4. (Optionally) Seed the database.

Seed the database (fresh installs only)

This is a destructive command; do not run it on an existing database!

Omnibus GitLab will not automatically seed your external database. Run the following command to import the schema and create the first admin user:

# Remove 'sudo' if you are the 'git' user
sudo gitlab-rake gitlab:setup

If you want to specify a password for the default root user, specify the initial_root_password setting in /etc/gitlab/gitlab.rb before running the gitlab:setup command above:

gitlab_rails['initial_root_password'] = 'nonstandardpassword'

If you want to specify the initial registration token for shared GitLab Runners, specify the initial_shared_runners_registration_token setting in /etc/gitlab/gitlab.rb before running the gitlab:setup command:

gitlab_rails['initial_shared_runners_registration_token'] = 'token'

Disabling automatic database migration

If you have multiple GitLab servers sharing a database, you will want to limit the number of nodes that are performing the migration steps during reconfiguration.

Edit /etc/gitlab/gitlab.rb:

# Enable or disable automatic database migrations
gitlab_rails['auto_migrate'] = false

Don't forget to remove the # comment characters at the beginning of this line.

Note: /etc/gitlab/gitlab.rb should have file permissions 0600 because it contains plain-text passwords.

The next time a reconfigure is triggered, the migration steps will not be performed.

Upgrade packaged PostgreSQL server

As of GitLab 10.0, PostgreSQL 9.6.X is the only database version in GitLab.

If you're still running on the bundled PostgreSQL 9.2.18 when you upgrade to GitLab 10.0, it will fail and remain on your current version. To ensure you're running the latest version of the bundled PostgreSQL, first upgrade GitLab to the latest 9.5.X release.

If you had previously avoided the upgrade by touching /etc/gitlab/skip-auto-migrations this will no longer work.

If you want to manually upgrade without upgrading GitLab, you can follow these instructions:

Note:

  • Please fully read this section before running any commands.
  • Please plan ahead as upgrade involves downtime.
  • If you encounter any problems during upgrade, please raise an issue with a full description at omnibus-gitlab issue tracker.

Before upgrading, please check the following:

  • You're currently running the latest version of GitLab and it is working.
  • If you recently upgraded, make sure that sudo gitlab-ctl reconfigure ran successfully before you proceed.
  • You're using the bundled version of PostgreSQL. Look for postgresql['enable'] to be true, commented out, or absent from /etc/gitlab/gitlab.rb.
  • You haven't already upgraded. Running sudo gitlab-psql --version should print psql (PostgreSQL) 9.2.18.
  • You will need to have sufficient disk space for two copies of your database. Do not attempt to upgrade unless you have enough free space available. Check your database size using sudo du -sh /var/opt/gitlab/postgresql/data (or update to your database path) and space available using sudo df -h. If the partition where the database resides does not have enough space, you can pass the argument --tmp-dir $DIR to the command.

Please note:

This upgrade requires downtime as the database must be down while the upgrade is being performed. The length of time depends on the size of your database. If you would rather avoid downtime, it is possible to upgrade to a new database using Slony. Please see our guide on how to perform the upgrade.

Once you have confirmed that the the above checklist is satisfied, you can proceed. To perform the upgrade, run the command:

sudo gitlab-ctl pg-upgrade

This command performs the following steps:

  1. Checks to ensure the database is in a known good state
  2. Shuts down the existing database, any unnecessary services, and enables the gitlab deploy page.
  3. Changes the symlinks in /opt/gitlab/embedded/bin/ for PostgreSQL to point to the newer version of the database
  4. Creates a new directory containing a new, empty database with a locale matching the existing database
  5. Uses the pg_upgrade tool to copy the data from the old database to the new database
  6. Moves the old database out of the way
  7. Moves the new database to the expected location
  8. Calls sudo gitlab-ctl reconfigure to do the required configuration changes, and start the new database server.
  9. Start the remaining services, and remove the deploy page.
  10. If any errors are detected during this process, it should immediately revert to the old version of the database.

Once this step is complete, verify everything is working as expected.

Once you have verified that your GitLab instance is running correctly, you can remove the old database with:

sudo rm -rf /var/opt/gitlab/postgresql/data.9.2.18

Upgrading a GitLab HA cluster

If PostgreSQL is configured for high availability, pg-upgrade should be run all the nodes running PostgreSQL. Other nodes can be skipped, but must be running the same GitLab version as the database nodes. Follow the steps below to upgrade the database nodes

  1. Secondary nodes must be upgraded before the primary node.
    1. On running pg-upgrade on a PG secondary node, the node will be removed from the cluster.
    2. Once all the secondary nodes are upgraded using pg-upgrade, the user will be left with a single-node cluster that has only the primary node.
    3. pg-upgrade, on secondary nodes will not update the existing data to match the new version, as that data will be replaced by the data from primary node. It will, however move the existing data to a backup location.
  2. Once all secondary nodes are upgraded, run pg-upgrade on primary node.
    1. On a primary node, pg-upgrade will update the existing data to match the new PG version.
  3. Recreate the secondary nodes by running the following command on each of them 
    gitlab-ctl repmgr standby setup MASTER_NODE_NAME
  4. Check if the repmgr cluster is back to the original state 
    gitlab-ctl repmgr cluster show

Upgrading a Geo instance

gitlab-ctl pg-upgrade command does not support Geo yet. This support will be added with GitLab 12.0

Troubleshooting upgrades in an HA cluster

  • If at some point, the bundled PostgreSQL had been running on a node before upgrading to an HA setup, the old data directory may remain. This will cause gitlab-ctl reconfigure to downgrade the version of the PostgreSQL utilities it uses on that node. Move (or remove) the directory to prevent this:
    • mv /var/opt/gitlab/postgresql/data/ /var/opt/gitlab/postgresql/data.$(date +%s)

Downgrade packaged PostgreSQL server

As of GitLab 10.0, the default version of PostgreSQL is 9.6.1, and 9.2.18 is no longer shipped in the package.

If you need to run an older version of PostgreSQL, you must downgrade GitLab to an older version.

Troubleshooting

Set MySQL collation to UTF-8

If you are hit by an error similar as described in this issue (Mysql2::Error: Incorrect string value (`st_diffs` field)), you can change the collation of the faulty table with:

ALTER TABLE merge_request_diffs default character set = utf8 collate = utf8_unicode_ci;
ALTER TABLE merge_request_diffs convert to character set utf8 collate utf8_unicode_ci;

In the above example the affected table is called merge_request_diffs.

Connecting to the bundled PostgreSQL database

If you need to connect to the bundled PostgreSQL database and are using the default Omnibus GitLab database configuration, you can connect as the application user:

sudo gitlab-rails dbconsole

or as a Postgres superuser:

sudo gitlab-psql -d gitlabhq_production