Migrate SVN to Git

Overview

You can migrate a DreamHost Subversion (SVN) repository to Git with git svn. The migration preserves your full commit history and maps SVN usernames to real Git author identities.

[server]$ git svn --version

Step 1 — Log in and locate your SVN repository

1. Log in to your server via SSH for the domain the SVN repo was configured on.

2. Navigate to your home directory:

   [server]$ cd ~

3. Confirm the svn directory is present:

   [server]$ ls ~/svn

   You should see your repository listed. For example:

   [server]$ ls ~/svn
   my_project

   Your SVN repository path generally follows this format:

   /home/username/svn/my_project

   The svn+ssh:// URL you will use in the steps below is constructed from your DreamHost username, the hostname you SSH into, and that path:

   svn+ssh://username@example.com/home/username/svn/my_project

   Replace username with your DreamHost username, example.com with the domain you SSH into, and my_project with your repository name.

Step 2 — Build an author mapping file

SVN commits record only a username. Git commits require a name and email address. Before cloning, create a mapping file that translates SVN usernames to Git author identities.

1. Run the following command to extract all unique SVN authors and write them to a file:

   [server]$ svn log -q svn+ssh://username@example.com/home/username/svn/my_project \
       | awk -F '|' '/^r/ {sub(" ","",$2); sub(" $","",$2); print $2" = "$2" <"$2"@example.com>"}' \
       | sort -u > ~/authors.txt

2. Open ~/authors.txt in a text editor and replace the placeholder names and email addresses with each contributor's real name and email. Each line must follow this format:

   svnusername = First Last <email@example.com>

   Example:

   jsmith = Jane Smith <jane.smith@example.com>

Step 3 — Clone the SVN repository

Use git svn clone to import the repository into a new local Git repo.

1. Run the clone command from your home directory:

   [server]$ git svn clone --no-metadata -A ~/authors.txt --stdlayout \
       svn+ssh://username@example.com/home/username/svn/my_project ~/git-migration

   Replace the SVN path and ~/git-migration with your repository path and preferred destination directory.

   This command:

   • Imports all commits with full history
   • Maps SVN usernames to Git authors using your authors.txt file (-A)
   • Strips git-svn tracking metadata from commit messages (--no-metadata)
   • Expects a standard SVN layout with trunk/, branches/, and tags/ directories (--stdlayout)

   If your repository does not use the standard trunk/branches/tags layout, see the Non-standard repository layouts section below.

2. Change into the new directory when the clone finishes:

   [server]$ cd ~/git-migration

3. Run git log to confirm the history imported correctly:

   [server]$ git log

Step 4 (Optional) — Convert svn:ignore to .gitignore

If your SVN repository used svn:ignore properties, convert them to a .gitignore file:

[server]$ git svn show-ignore > .gitignore
[server]$ git add .gitignore
[server]$ git commit -m "Convert svn:ignore to .gitignore"

Step 5 — Fix branches and tags

git svn imports SVN branches and tags as remote-tracking branches rather than native Git branches and tags. This step converts them to proper Git references and renames trunk to main.

1. Rename the trunk branch to main:

   [server]$ git branch -m trunk main

2. Convert SVN tag branches to real Git tags. Adjust the ref path to match what git branch -a shows for your repository:

   [server]$ git for-each-ref --format='%(refname:short)' refs/remotes/origin/tags \
       | sed 's#origin/tags/##' \
       | while read t; do git tag "$t" "refs/remotes/origin/tags/$t"; done

   Run git tag to confirm the tags were created.

Step 6 — Push to your new Git repository

You can host the new repository on your DreamHost account over SSH. See Set up a Git repository for DreamHost-hosted options.

1. Add your Git remote:

   [server]$ git remote add origin git-repository-url

2. Push all branches:

   [server]$ git push --all origin

3. Push all tags:

   [server]$ git push --tags origin

Your migration is complete. You can now use standard Git commands to manage the repository.

How do I clean up the SVN repository?

Once you have confirmed the migration is complete, you can remove the SVN repository from your DreamHost account to free up disk space:

[server]$ rm -rf ~/svn/my_project

Non-standard repository layouts

If your SVN repository does not follow the standard trunk/branches/tags layout, use the -T, -b, and -t flags to specify the paths manually instead of --stdlayout:

• -T -- path to trunk (default: trunk)
• -b -- path to branches (default: branches)
• -t -- path to tags (default: tags)

For more granular control -- for example, to import only a specific branch -- you can separate the initialization and fetch steps:

[server]$ git svn init svn+ssh://username@example.com/home/username/svn/my_project ~/git-migration
[server]$ cd ~/git-migration
[server]$ git svn fetch

See the git svn documentation for all available options.

FAQs

Does the migration preserve the full commit history?

What if a commit author is missing from authors.txt?

Can I migrate only a specific branch instead of the entire repository?

See also

DreamHost links

• Subversion overview
• Backing up your SVN repository
• Set up a Git repository
• SSH overview

Third-party links

• git svn documentation