• Configure the external URL for GitLab
  • Specify the external URL at the time of installation
• Configure a relative URL for GitLab
• Load external configuration file from non-root user
• Read certificate from file
• Store Git data in an alternative directory
• Change the name of the Git user or group
• Specify numeric user and group identifiers
• Disable user and group account management
• Move the home directory for a user
• Disable storage directories management
  • Disable the /etc/gitlab directory management
  • Disable the /var/opt/gitlab directory management
• Start Linux package installation services only after a given file system is mounted
• Configure the runtime directory
• Configure a failed authentication ban
• Disable automatic cache cleaning during installation
• Error Reporting and Logging with Sentry
• Set a Content Delivery Network URL
• Set a Content Security Policy
• Set initial root password on installation
• Set allowed hosts to prevent host header attacks
• Related topics
• Troubleshooting
  • Relative URL troubleshooting
  • Mixlib::ShellOut::ShellCommandFailed: linux_user[GitLab user and group]

Configuration options for Linux package installations

To configure GitLab, set the relevant options in the /etc/gitlab/gitlab.rb file.

gitlab.rb.template contains a complete list of available options. New installations have all the options of the template listed in /etc/gitlab/gitlab.rb by default.

For a list of default settings, see the package defaults.

Configure the external URL for GitLab

To display the correct repository clone links to your users, you must provide GitLab with the URL your users use to reach the repository. You can use the IP of your server, but a Fully Qualified Domain Name (FQDN) is preferred. See the DNS documentation for more details about the use of DNS in a self-managed GitLab instance.

To change the external URL:

1. Optional. Before you change the external URL, determine if you have previously defined a custom Home page URL or After sign-out path. Both of these settings might cause unintentional redirecting after configuring a new external URL. If you have defined any URLs, remove them completely.

2. Edit /etc/gitlab/gitlab.rb and change external_url to your preferred URL:

   external_url "http://gitlab.example.com"
   

   Alternatively, you can use the IP address of your server:

   external_url "http://10.0.0.1"
   

   In the previous examples we use plain HTTP. If you want to use HTTPS, see how to configure SSL.

3. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

4. Optional. If you had been using GitLab for a while, after you change the external URL, you should also invalidate the Markdown cache.

Specify the external URL at the time of installation

If you use the Linux package, you can set up your GitLab instance with the minimum number of commands by using the EXTERNAL_URL environment variable. If this variable is set, it is automatically detected and its value is written as external_url in the gitlab.rb file.

The EXTERNAL_URL environment variable affects only the installation and upgrade of packages. For regular reconfigure runs, the value in /etc/gitlab/gitlab.rb is used.

As part of package updates, if you have EXTERNAL_URL variable set inadvertently, it replaces the existing value in /etc/gitlab/gitlab.rb without any warning. So, we recommended not to set the variable globally, but rather pass it specifically to the installation command:

sudo EXTERNAL_URL="https://gitlab.example.com" apt-get install gitlab-ee

Configure a relative URL for GitLab

While we recommended installing GitLab in its own (sub)domain, sometimes it is not possible. In that case, GitLab can also be installed under a relative URL, for example, https://example.com/gitlab.

By changing the URL, all remote URLs change as well, so you must manually edit them in any local repository that points to your GitLab instance.

To enable relative URL in GitLab:

1. Set the external_url in /etc/gitlab/gitlab.rb:

   external_url "https://example.com/gitlab"
   

   In this example, the relative URL under which GitLab is served is /gitlab. Change it to your liking.

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

If you have any issues, see the troubleshooting section.

Load external configuration file from non-root user

Linux package installations load all configuration from /etc/gitlab/gitlab.rb file. This file has strict file permissions and is owned by the root user. The reason for strict permissions and ownership is that /etc/gitlab/gitlab.rb is being executed as Ruby code by the root user during gitlab-ctl reconfigure. This means that users who have to write access to /etc/gitlab/gitlab.rb can add a configuration that is executed as code by root.

In certain organizations, it is allowed to have access to the configuration files but not as the root user. You can include an external configuration file inside /etc/gitlab/gitlab.rb by specifying the path to the file:

from_file "/home/admin/external_gitlab.rb"

Code you include into /etc/gitlab/gitlab.rb using from_file runs with root privileges when you run sudo gitlab-ctl reconfigure. Any configuration that is set in /etc/gitlab/gitlab.rb after from_file is included, takes precedence over the configuration from the included file.

Read certificate from file

Certificates can be stored as separate files and loaded into memory when running sudo gitlab-ctl reconfigure. Files containing certificates must be plaintext.

In this example, the PostgreSQL server certificate is read directly from a file rather than copy and pasting into the gitlab.rb directly.

postgresql['internal_certificate'] = File.read('/path/to/server.crt')

Store Git data in an alternative directory

By default, Linux package installations store the Git repository data under /var/opt/gitlab/git-data. The repositories are stored in a subfolder called repositories.

To change the location of the git-data parent directory:

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

   git_data_dirs({ "default" => { "path" => "/mnt/nas/git-data" } })
   

   You can also add more than one Git data directory:

   git_data_dirs({
     "default" => { "path" => "/var/opt/gitlab/git-data" },
     "alternative" => { "path" => "/mnt/nas/git-data" }
   })
   

   The target directories and any of its subpaths must not be a symlink.

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

3. Optional. If you already have existing Git repositories in /var/opt/gitlab/git-data, you can move them to the new location:

   1. Prevent users from writing to the repositories while you move them:

      sudo gitlab-ctl stop
      

   2. Sync the repositories to the new location. Note there is no slash behind repositories, but there is a slash behind git-data:

      sudo rsync -av --delete /var/opt/gitlab/git-data/repositories /mnt/nas/git-data/
      

   3. Reconfigure to start the necessary processes and fix any wrong permissions:

      sudo gitlab-ctl reconfigure
      

   4. Double-check the directory layout in /mnt/nas/git-data/. The expected output should be repositories:

      sudo ls /mnt/nas/git-data/
      

   5. Start GitLab and verify that you can browse through the repositories in the web interface:

      sudo gitlab-ctl start
      

If you’re running Gitaly on a separate server, remember to also include the gitaly_address for each Git data directory. See the documentation on configuring Gitaly.

If you’re not looking to move all repositories, but instead want to move specific projects between existing repository storages, use the Edit Project API endpoint and specify the repository_storage attribute.

Change the name of the Git user or group

By default, Linux package installations use the user name git for Git GitLab Shell login, ownership of the Git data itself, and SSH URL generation on the web interface. Similarly, the git group is used for group ownership of the Git data.

To change the user and group:

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

   user['username'] = "gitlab"
   user['group'] = "gitlab"
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

If you are changing the username of an existing installation, the reconfigure run doesn’t change the ownership of the nested directories, so you must do that manually. Make sure that the new user can access the repositories and uploads directories.

Specify numeric user and group identifiers

Linux package installations create users for GitLab, PostgreSQL, Redis, NGINX, etc. To specify the numeric identifiers for these users:

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

   user['uid'] = 1234
   user['gid'] = 1234
   postgresql['uid'] = 1235
   postgresql['gid'] = 1235
   redis['uid'] = 1236
   redis['gid'] = 1236
   web_server['uid'] = 1237
   web_server['gid'] = 1237
   registry['uid'] = 1238
   registry['gid'] = 1238
   mattermost['uid'] = 1239
   mattermost['gid'] = 1239
   prometheus['uid'] = 1240
   prometheus['gid'] = 1240
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

3. Optional. If you’re changing user['uid'] and user['gid'], make sure to update the uid/guid of any files not managed by the Linux package directly, for example, the logs:

find /var/log/gitlab -uid <old_uid> | xargs -I:: chown git ::
find /var/log/gitlab -gid <old_uid> | xargs -I:: chgrp git ::
find /var/opt/gitlab -uid <old_uid> | xargs -I:: chown git ::
find /var/opt/gitlab -gid <old_uid> | xargs -I:: chgrp git ::

Disable user and group account management

By default, Linux package installations create system user and group accounts, as well as keeping the information updated. These system accounts run various components of the package. Most users don’t need to change this behavior. However, if your system accounts are managed by other software, for example, LDAP, you might need to disable account management done by the GitLab package.

By default, the Linux package installations expect the following users and groups to exist:

To disable user and group accounts management:

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

   manage_accounts['enable'] = false
   

2. Optional. You can also use different user/group names, but then you must specify the user/group details:

   # GitLab
   user['username'] = "custom-gitlab"
   user['group'] = "custom-gitlab"
   user['shell'] = "/bin/sh"
   user['home'] = "/var/opt/custom-gitlab"
   
   # Web server
   web_server['username'] = 'webserver-gitlab'
   web_server['group'] = 'webserver-gitlab'
   web_server['shell'] = '/bin/false'
   web_server['home'] = '/var/opt/gitlab/webserver'
   
   # Postgresql (not needed when using external Postgresql)
   postgresql['username'] = "postgres-gitlab"
   postgresql['group'] = "postgres-gitlab"
   postgresql['shell'] = "/bin/sh"
   postgresql['home'] = "/var/opt/postgres-gitlab"
   
   # Redis (not needed when using external Redis)
   redis['username'] = "redis-gitlab"
   redis['group'] = "redis-gitlab"
   redis['shell'] = "/bin/false"
   redis['home'] = "/var/opt/redis-gitlab"
   
   # And so on for users/groups for GitLab Mattermost
   

3. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Move the home directory for a user

For the GitLab user, we recommended that the home directory is set on a local disk and not on shared storage like NFS, for better performance. When setting it in NFS, Git requests must make another network request to read the Git configuration and this increases latency in Git operations.

To move an existing home directory, GitLab services need to be stopped and some downtime is required:

1. Stop GitLab:

   gitlab-ctl stop
   

2. Stop the runit server:

   sudo systemctl stop gitlab-runsvdir
   

3. Change the home directory:

   usermod -d /path/to/home <username>
   

   If you had existing data, you need to manually copy/rsync it to the new location:

4. Edit /etc/gitlab/gitlab.rb:

   user['home'] = "/var/opt/custom-gitlab"
   

5. Start the runit server:

   sudo systemctl start gitlab-runsvdir
   

6. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Disable storage directories management

The Linux package takes care of creating all the necessary directories with the correct ownership and permissions, as well as keeping this updated.

Some of the directories hold large amounts of data so in certain setups, those directories are most likely mounted on an NFS (or some other) share.

Some types of mounts don’t allow the automatic creation of directories by the root user (default user for initial setup), for example, NFS with root_squash enabled on the share. To work around this, the Linux package attempts to create those directories using the directory’s owner user.

Disable the /etc/gitlab directory management

If you have the /etc/gitlab directory mounted, you can turn off the management of that directory:

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

   manage_storage_directories['manage_etc'] = false
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Disable the /var/opt/gitlab directory management

If you are mounting all GitLab storage directories, each on a separate mount, you should completely disable the management of storage directories.

Linux package installations expect these directories to exist on the file system. It is up to you to create and set correct permissions if this setting is set.

Enabling this setting prevents the creation of the following directories:

To disable the management of storage directories:

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

   manage_storage_directories['enable'] = false
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Start Linux package installation services only after a given file system is mounted

If you want to prevent Linux package installation services (NGINX, Redis, Puma, etc.) from starting before a given file system is mounted:

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

   # wait for /var/opt/gitlab to be mounted
   high_availability['mountpoint'] = '/var/opt/gitlab'
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Configure the runtime directory

When Prometheus monitoring is enabled, the GitLab Exporter conducts measurements of each Puma process (Rails metrics). Every Puma process needs to write a metrics file to a temporary location for each controller request. Prometheus then collects all these files and processes their values.

To avoid creating disk I/O, the Linux package uses a runtime directory.

During reconfigure, the package check if /run is a tmpfs mount. If it is not, the following warning is shown and Rails metrics are disabled:

Runtime directory '/run' is not a tmpfs mount.

To enable the Rails metrics again:

1. Edit /etc/gitlab/gitlab.rb to create a tmpfs mount (note that there is no = in the configuration):

   runtime_dir '/path/to/tmpfs'
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Configure a failed authentication ban

You can configure a failed authentication ban for Git and the container registry:

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

   gitlab_rails['rack_attack_git_basic_auth'] = {
     'enabled' => true,
     'ip_whitelist' => ["127.0.0.1"],
     'maxretry' => 10, # Limit the number of Git HTTP authentication attempts per IP
     'findtime' => 60, # Reset the auth attempt counter per IP after 60 seconds
     'bantime' => 3600 # Ban an IP for one hour (3600s) after too many auth attempts
   }
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

The following settings can be configured:

• enabled: By default, this is set to false. Set this to true to enable Rack Attack.
• ip_whitelist: IPs to not block. They must be formatted as strings in a Ruby array. CIDR notation is supported in GitLab 12.1 and later. For example, ["127.0.0.1", "127.0.0.2", "127.0.0.3", "192.168.0.1/24"].
• maxretry: The maximum amount of times a request can be made in the specified time.
• findtime: The maximum amount of time that failed requests can count against an IP before it’s added to the denylist (in seconds).
• bantime: The total amount of time that an IP is blocked (in seconds).

Disable automatic cache cleaning during installation

If you have a large GitLab installation, you might not want to run a rake cache:clear task as it can take a long time to finish. By default, the cache clear task runs automatically during reconfiguring.

To disable automatic cache cleaning during installation:

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

   # This is an advanced feature used by large gitlab deployments where loading
   # whole RAILS env takes a lot of time.
   gitlab_rails['rake_cache_clear'] = false
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Error Reporting and Logging with Sentry

Sentry is an error reporting and logging tool which can be used as SaaS or on-premise. It’s Open Source, and you can browse its source code repositories.

To configure Sentry:

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

   gitlab_rails['sentry_enabled'] = true
   gitlab_rails['sentry_dsn'] = 'https://<key>@sentry.io/<project>'
   gitlab_rails['sentry_clientside_dsn'] = 'https://<key>@sentry.io/<project>'
   gitlab_rails['sentry_environment'] = 'production'
   

   The Sentry environment can be used to track errors and issues across several deployed GitLab environments, for example, lab, development, staging, and production.

2. Optional. To set custom Sentry tags on every event sent from a particular server, the GITLAB_SENTRY_EXTRA_TAGS an environment variable can be set. This variable is a JSON-encoded hash representing any tags that should be passed to Sentry for all exceptions from that server.

   For instance, setting:

   gitlab_rails['env'] = {
     'GITLAB_SENTRY_EXTRA_TAGS' => '{"stage": "main"}'
   }
   

   Would add the stage tag with a value of main.

3. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Set a Content Delivery Network URL

Service static assets with a Content Delivery Network (CDN) or asset host using gitlab_rails['cdn_host']. This configures a Rails asset host.

To set a CDN/asset host:

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

   gitlab_rails['cdn_host'] = 'https://mycdnsubdomain.fictional-cdn.com'
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Additional documentation for configuring common services to act as an asset host is tracked in this issue.

Set a Content Security Policy

Setting a Content Security Policy (CSP) can help thwart JavaScript cross-site scripting (XSS) attacks. See the Mozilla documentation on CSP for more details.

GitLab 12.2 added support for CSP and nonce-source with inline JavaScript. It is not configured by default yet.

To add a CSP:

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

   gitlab_rails['content_security_policy'] = {
       enabled: true,
       report_only: false
   }
   

   GitLab automatically provides secure default values for the CSP. Explicitly setting the <default_value> value for a directive is equivalent to not setting a value and will use the default values.

   To add a custom CSP:

   gitlab_rails['content_security_policy'] = {
       enabled: true,
       report_only: false,
       directives: {
         default_src: "'none'",
         script_src: "https://example.com"
       }
   }
   

   In GitLab 14.9 and later, secure default values are used for directives that aren’t explicitly configured.

   To unset a CSP directive, set a value of false.

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

Set initial root password on installation

The initial password for the administrator user root can be set at installation time. For more information, see Set up the initial password.

Set allowed hosts to prevent host header attacks

To prevent GitLab from accepting a host header other than what’s intended:

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

   gitlab_rails['allowed_hosts'] = ['gitlab.example.com']
   

2. Reconfigure GitLab:

   sudo gitlab-ctl reconfigure
   

There are no known security issues in GitLab caused by not configuring allowed_hosts, but it’s recommended for defense in depth against potential HTTP Host header attacks.

If using a custom external proxy such as Apache, it may be necessary to add the localhost address or name (localhost or 127.0.0.1). You should add filters to the external proxy to mitigate potential HTTP Host header attacks passed through the proxy to workhorse.

gitlab_rails['allowed_hosts'] = ['gitlab.example.com', '127.0.0.1', 'localhost']

Related topics

• Disable impersonation
• Set up LDAP sign-in
• Smartcard authentication
• Set up NGINX for things like:
  • Set up HTTPS
  • Redirect HTTP requests to HTTPS
  • Change the default port and the SSL certificate locations
  • Set the NGINX listen-address or addresses
  • Insert custom NGINX settings into the GitLab server block
  • Insert custom settings into the NGINX configuration
  • Enable nginx_status
• Use a non-packaged web-server
• Use a non-packaged PostgreSQL database management server
• Use a non-packaged Redis instance
• Add ENV vars to the GitLab runtime environment
• Changing gitlab.yml and application.yml settings
• Send application email via SMTP
• Set up OmniAuth (Google, Twitter, GitHub login)
• Adjust Puma settings

Troubleshooting

Relative URL troubleshooting

If you notice any issues with GitLab assets appearing broken after moving to a relative URL configuration (like missing images or unresponsive components), please raise an issue in GitLab with the Frontend label.

Mixlib::ShellOut::ShellCommandFailed: linux_user[GitLab user and group]

When moving the home directory for a user, if the runit service is not stopped and the home directories are not manually moved for the user, GitLab will encounter an error while reconfiguring:

account[GitLab user and group] (gitlab::users line 28) had an error: Mixlib::ShellOut::ShellCommandFailed: linux_user[GitLab user and group] (/opt/gitlab/embedded/cookbooks/cache/cookbooks/package/resources/account.rb line 51) had an error: Mixlib::ShellOut::ShellCommandFailed: Expected process to exit with [0], but received '8'
---- Begin output of ["usermod", "-d", "/var/opt/gitlab", "git"] ----
STDOUT:
STDERR: usermod: user git is currently used by process 1234
---- End output of ["usermod", "-d", "/var/opt/gitlab", "git"] ----
Ran ["usermod", "-d", "/var/opt/gitlab", "git"] returned 8

Make sure to stop runit before moving the home directory.