• How pull mirroring works
• Configure pull mirroring
  • Overwrite diverged branches
  • Trigger pipelines for mirror updates
• Trigger an update by using the API
• Fix hard failures when mirroring
• Related topics

Pull from a remote repository

You can use the GitLab interface to browse the content and activity of a repository, even if it isn’t hosted on GitLab. Create a pull mirror to copy the branches, tags, and commits from an upstream repository to yours.

Unlike push mirrors, pull mirrors retrieve changes from an upstream (remote) repository on a scheduled basis. To prevent the mirror from diverging from the upstream repository, don’t push commits directly to the downstream mirror. Push commits to the upstream repository instead. Changes in the remote repository are pulled into the GitLab repository:

• Automatically, 30 minutes after a previous pull. This cannot be disabled.
• When an administrator force-updates the mirror.
• When an API call triggers an update.

UI and API updates are subject to default pull mirroring intervals of 5 minutes. This interval can be configured by self-managed instances.

By default, if any branch or tag on the downstream pull mirror diverges from the local repository, GitLab stops updating the branch. This prevents data loss. Deleted branches and tags in the upstream repository are not reflected in the downstream repository.

How pull mirroring works

After you configure a GitLab repository as a pull mirror:

1. GitLab adds the repository to a queue.
2. Once per minute, a Sidekiq cron job schedules repository mirrors to update, based on:
   • Available capacity, determined by Sidekiq settings. For GitLab.com, read GitLab.com Sidekiq settings.
   • How many mirrors are already in the queue and due for updates. Being due depends on when the repository mirror was last updated, and how many times updates have been retried.
3. Sidekiq becomes available to process updates, mirrors are updated. If the update process:
   • Succeeds: An update is enqueued again with at least a 30 minute wait.
   • Fails: The update is attempted again later. After 14 failures, a mirror is marked as a hard failure and is no longer enqueued for updates. A branch diverging from its upstream counterpart can cause failures. To prevent branches from diverging, configure Overwrite diverged branches when you create your mirror.

Configure pull mirroring

Prerequisites:

• If your remote repository is on GitHub and you have two-factor authentication (2FA) configured, create a personal access token for GitHub with the repo scope. If 2FA is enabled, this personal access token serves as your GitHub password.
• GitLab Silent Mode is not enabled.

1. On the left sidebar, select Search or go to and find your project.
2. Select Settings > Repository.
3. Expand Mirroring repositories.

4. Enter the Git repository URL.

   To mirror the gitlab repository, use gitlab.com:gitlab-org/gitlab.git or https://gitlab.com/gitlab-org/gitlab.git.
5. In Mirror direction, select Pull.
6. In Authentication method, select your authentication method. For more information, see Authentication methods for mirrors.
7. Select any of the options you need:
   • Overwrite diverged branches
   • Trigger pipelines for mirror updates
   • Only mirror protected branches
8. To save the configuration, select Mirror repository.

Overwrite diverged branches

To always update your local branches with remote versions, even if they have diverged from the remote, select Overwrite diverged branches when you create a mirror.

Trigger pipelines for mirror updates

If this option is enabled, pipelines trigger when branches or tags are updated from the remote repository. Depending on the activity of the remote repository, this may greatly increase the load on your CI runners. Only enable this feature if you know they can handle the load. CI uses the credentials assigned when you set up pull mirroring.

Trigger an update by using the API

Pull mirroring uses polling to detect new branches and commits added upstream, often minutes afterwards. You can notify GitLab using an API call, but the minimum interval for pull mirroring limits is still enforced.

For more information, read Start the pull mirroring process for a project.

Fix hard failures when mirroring

After 14 consecutive unsuccessful retries, the mirroring process is marked as a hard failure and mirroring attempts stop. This failure is visible in either the:

• Project’s main dashboard.
• Pull mirror settings page.

To resume project mirroring, force an update.

If multiple projects are affected by this problem, such as after a long network or server outage, you can use the Rails console to identify and update all affected projects with this command:

Project.find_each do |p|
  if p.import_state && p.import_state.retry_count >= 14
    puts "Resetting mirroring operation for #{p.full_path}"
    p.import_state.reset_retry_count
    p.import_state.set_next_execution_to_now(prioritized: true)
    p.import_state.save!
  end
end

Related topics

• Troubleshooting for repository mirroring.
• Pull mirroring intervals
• Pull mirroring API