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| stage | group | info | type |
|---|---|---|---|
| Create | Gitaly | To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments | reference |
Moving repositories managed by GitLab (CORE ONLY)
Sometimes you need to move all repositories managed by GitLab to another file system or another server.
Moving data within 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. Within this
example, additional storage called
storage1andstorage2is configured. - The API documentation details the endpoints for querying and scheduling repository moves.
- Migrate existing repositories to Gitaly Cluster.
Limitations
Read more in the API documentation.
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 datacenter 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- The target directory contains an outdated copy of the repositories.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
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's files using tools like rsync.
- From GitLab 13.3, backup performance can be improved by processing multiple repositories concurrently.
- Backups can be created of just the repositories using the skip feature.
Target directory is empty: use a tar pipe
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
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 / 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. This utility
is either already installed on your system or easily installable
via apt, yum, and so on.
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
easily get the wrong directory structure in the target directory.
If you want to see progress, replace -a with -av.
Single rsync to another server
WARNING:
Using rsync to migrate Git data can cause data loss and repository corruption.
These instructions are being reviewed.
If the git user on your source system has SSH access to the target
server you can send the repositories over the network with rsync.
sudo -u git sh -c 'rsync -a --delete /var/opt/gitlab/git-data/repositories/. \
git@newserver:/mnt/gitlab/repositories'
Thousands of Git repositories: use one rsync per repository
WARNING:
Using rsync to migrate Git data can cause data loss and repository corruption.
These instructions are being reviewed.
Every time you start an rsync job it has to inspect all files in
the source directory, all files in the target directory, and then
decide what files to copy or not. If the source or target directory
has many contents this startup phase of rsync can become a burden
for your GitLab server. In cases like this you can make rsync's
life easier by dividing its work in smaller pieces, and sync one
repository at a time.
In addition to rsync we use GNU Parallel.
This utility is not included in GitLab so you need to install it yourself with apt
or yum. Also note that the GitLab scripts we used below were added in GitLab 8.1.
This process does not clean up repositories at the target location that no longer exist at the source.
Parallel rsync for all repositories known to GitLab
WARNING:
Using rsync to migrate Git data can cause data loss and repository corruption.
These instructions are being reviewed.
This syncs repositories with 10 rsync processes at a time. We keep
track of progress so that the transfer can be restarted if necessary.
First we create a new directory, owned by git, to hold transfer
logs. We assume the directory is empty before we start the transfer
procedure, and that we are the only ones writing files in it.
# Omnibus
sudo mkdir /var/opt/gitlab/transfer-logs
sudo chown git:git /var/opt/gitlab/transfer-logs
# Source
sudo -u git -H mkdir /home/git/transfer-logs
We seed the process with a list of the directories we want to copy.
# Omnibus
sudo -u git sh -c 'gitlab-rake gitlab:list_repos > /var/opt/gitlab/transfer-logs/all-repos-$(date +%s).txt'
# Source
cd /home/git/gitlab
sudo -u git -H sh -c 'bundle exec rake gitlab:list_repos > /home/git/transfer-logs/all-repos-$(date +%s).txt'
Now we can start the transfer. The command below is idempotent, and
the number of jobs done by GNU Parallel should converge to zero. If it
does not, some repositories listed in all-repos-1234.txt may have been
deleted/renamed before they could be copied.
# Omnibus
sudo -u git sh -c '
cat /var/opt/gitlab/transfer-logs/* | sort | uniq -u |\
/usr/bin/env JOBS=10 \
/opt/gitlab/embedded/service/gitlab-rails/bin/parallel-rsync-repos \
/var/opt/gitlab/transfer-logs/success-$(date +%s).log \
/var/opt/gitlab/git-data/repositories \
/mnt/gitlab/repositories
'
# Source
cd /home/git/gitlab
sudo -u git -H sh -c '
cat /home/git/transfer-logs/* | sort | uniq -u |\
/usr/bin/env JOBS=10 \
bin/parallel-rsync-repos \
/home/git/transfer-logs/success-$(date +%s).log \
/home/git/repositories \
/mnt/gitlab/repositories
`
Parallel rsync only for repositories with recent activity
WARNING:
Using rsync to migrate Git data can cause data loss and repository corruption.
These instructions are being reviewed.
Suppose you have already done one sync that started after 2015-10-1 12:00 UTC.
Then you might only want to sync repositories that were changed via GitLab
after that time. You can use the SINCE variable to tell rake gitlab:list_repos to only print repositories with recent activity.
# Omnibus
sudo gitlab-rake gitlab:list_repos SINCE='2015-10-1 12:00 UTC' |\
sudo -u git \
/usr/bin/env JOBS=10 \
/opt/gitlab/embedded/service/gitlab-rails/bin/parallel-rsync-repos \
success-$(date +%s).log \
/var/opt/gitlab/git-data/repositories \
/mnt/gitlab/repositories
# Source
cd /home/git/gitlab
sudo -u git -H bundle exec rake gitlab:list_repos SINCE='2015-10-1 12:00 UTC' |\
sudo -u git -H \
/usr/bin/env JOBS=10 \
bin/parallel-rsync-repos \
success-$(date +%s).log \
/home/git/repositories \
/mnt/gitlab/repositories