Moving repositories managed by GitLab

DETAILS: Tier: Free, Premium, Ultimate Offering: Self-managed

You can move all repositories managed by GitLab to another file system or another server.

Moving data in a GitLab instance

The GitLab API is the recommended way to move Git repositories:

Between servers.
Between different storage.
From single-node Gitaly to Gitaly Cluster.

For more information, see:

Configuring additional storage for Gitaly. This example configures additional storage called storage1 and storage2.
The API documentation details the endpoints for querying and scheduling project repository moves.
The API documentation details the endpoints for querying and scheduling snippet repository moves.
The API documentation details the endpoints for querying and scheduling group repository moves.
Migrate to Gitaly Cluster.

Moving Repositories

GitLab repositories can be associated with projects, groups, and snippets. Each of these types has a separate API to schedule the respective repositories to move. To move all repositories on a GitLab instance, each of these types must be scheduled to move for each storage.

Each repository is made read-only for the duration of the move. The repository is not writable until the move has completed.

To move repositories:

Ensure all local and cluster storages are accessible to the GitLab instance. In this example, these are <original_storage_name> and <cluster_storage_name>.
Configure repository storage weights so that the new storages receives all new projects. This stops new projects from being created on existing storages while the migration is in progress.
Schedule repository moves for:
- All projects or individual projects.
- All snippets or individual snippets.
- All groups or individual groups.
If Geo is enabled, resync all repositories.

Move all projects

To move all projects by using the API:

Schedule repository storage moves for all projects on a storage shard using the API. For example:

curl --request POST --header "Private-Token: <your_access_token>" \
     --header "Content-Type: application/json" \
     --data '{"source_storage_name":"<original_storage_name>","destination_storage_name":"<cluster_storage_name>"}' \
     "https://gitlab.example.com/api/v4/project_repository_storage_moves"

Query the most recent repository moves using the API. The response indicates either:
- The moves have completed successfully. The state field is finished.
- The moves are in progress. Re-query the repository move until it completes successfully.
- The moves have failed. Most failures are temporary and are solved by rescheduling the move.
After the moves are complete, use the API to query projects and confirm that all projects have moved. None of the projects should be returned with the repository_storage field set to the old storage. For example:
```
curl --header "Private-Token: <your_access_token>" --header "Content-Type: application/json" \
"https://gitlab.example.com/api/v4/projects?repository_storage=<original_storage_name>"
```
Alternatively use the rails console to confirm that all projects have moved. Run the following in the rails console:
```
ProjectRepository.for_repository_storage('<original_storage_name>')
```
Repeat for each storage as required.

Move all snippets

To move all snippets by using the API:

Schedule repository storage moves for all snippets on a storage shard. For example:

curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" \
     --header "Content-Type: application/json" \
     --data '{"source_storage_name":"<original_storage_name>","destination_storage_name":"<cluster_storage_name>"}' \
     "https://gitlab.example.com/api/v4/snippet_repository_storage_moves"

Query the most recent repository moves. The response indicates either:
- The moves have completed successfully. The state field is finished.
- The moves are in progress. Re-query the repository move until it completes successfully.
- The moves have failed. Most failures are temporary and are solved by rescheduling the move.
After the moves are complete, use the rails console to confirm that all snippets have moved. No snippets should be returned for the original storage. Run the following in the rails console:
```
SnippetRepository.for_repository_storage('<original_storage_name>')
```
Repeat for each storage as required.

Move all groups

DETAILS: Tier: Premium, Ultimate Offering: Self-managed

To move all groups by using the API:

Schedule repository storage moves for all groups on a storage shard. For example:

curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" \
     --header "Content-Type: application/json" \
     --data '{"source_storage_name":"<original_storage_name>","destination_storage_name":"<cluster_storage_name>"}' \
     "https://gitlab.example.com/api/v4/group_repository_storage_moves"

Query the most recent repository moves. The response indicates either:
- The moves have completed successfully. The state field is finished.
- The moves are in progress. Re-query the repository move until it completes successfully.
- The moves have failed. Most failures are temporary and are solved by rescheduling the move.
After the moves are complete, use the rails console to confirm that all groups have moved. No groups should be returned for the original storage. Run the following in the rails console:
```
GroupWikiRepository.for_repository_storage('<original_storage_name>')
```
Repeat for each storage as required.

Migrating to another GitLab instance

Using the API isn't an option if you are migrating to a new GitLab environment, for example:

From a single-node GitLab to a scaled-out architecture.
From a GitLab instance in your private data center to a cloud provider.

The rest of the document looks at some of the ways you can copy all your repositories from /var/opt/gitlab/git-data/repositories to /mnt/gitlab/repositories.

We look at three scenarios:

The target directory is empty.
The target directory contains an outdated copy of the repositories.
How to deal with thousands of repositories.

WARNING: Each of the approaches we list can or does overwrite data in the target directory /mnt/gitlab/repositories. Do not mix up the source and the target.

Recommended approach in all cases

For either Gitaly or Gitaly Cluster targets, the GitLab backup and restore capability should be used. Git repositories are accessed, managed, and stored on GitLab servers by Gitaly as a database. Data loss can result from directly accessing and copying Gitaly files using tools like rsync.

Backup performance can be improved by processing multiple repositories concurrently.
Backups can be created of just the repositories using the skip feature.

No other method works for Gitaly Cluster targets.

Target directory is empty: use a `tar` pipe

For Gitaly targets (use recommended approach for Gitaly Cluster targets), if the target directory /mnt/gitlab/repositories is empty the simplest thing to do is to use a tar pipe. This method has low overhead and tar is almost always already installed on your system.

However, it is not possible to resume an interrupted tar pipe; if that happens then all data must be copied again.

sudo -u git sh -c 'tar -C /var/opt/gitlab/git-data/repositories -cf - -- . |\
  tar -C /mnt/gitlab/repositories -xf -'

If you want to see progress, replace -xf with -xvf.

`tar` pipe to another server

For Gitaly targets (use recommended approach for Gitaly Cluster targets), you can also use a tar pipe to copy data to another server. If your git user has SSH access to the new server as git@newserver, you can pipe the data through SSH.

sudo -u git sh -c 'tar -C /var/opt/gitlab/git-data/repositories -cf - -- . |\
  ssh git@newserver tar -C /mnt/gitlab/repositories -xf -'

If you want to compress the data before it goes over the network (which costs you CPU cycles) you can replace ssh with ssh -C.

The target directory contains an outdated copy of the repositories: use `rsync`

WARNING: Using rsync to migrate Git data can cause data loss and repository corruption. These instructions are being reviewed.

If the target directory already contains a partial or outdated copy of the repositories it may be wasteful to copy all the data again with tar. In this scenario it is better to use rsync for Gitaly targets (use recommended approach for Gitaly Cluster targets).

This utility is either already installed on your system, or installable using apt or yum.

sudo -u git  sh -c 'rsync -a --delete /var/opt/gitlab/git-data/repositories/. \
  /mnt/gitlab/repositories'

The /. in the command above is very important, without it you can get the wrong directory structure in the target directory. If you want to see progress, replace -a with -av.

Single `rsync` to another server