Creating a Git Remote Repository on Server

This article will introduce how to create a central git server on a remote server and configure ssh connections.

Requirements

• git
• ssh

Create a git User

On remote server, we usually create a user named git to manage the git repositories. We can use the following command to create a git user:

# -m to create a home directory for the user
useradd -m git

Then we need to set a password for the git user:

# This command may require your `sudo` password the first time,
# then you will be prompted to enter the new password twice
sudo passwd git

Configuration

Create a .ssh Directory

We need to set up ssh for the git user so that we can connect to the git server via ssh.

# Switch to the `git` user, if not already done
su git
# Make sure the ~/.ssh directory and authorized_keys file exist and have the correct permissions
cd ~
mkdir -p .ssh && chmod 700 .ssh
touch .ssh/authorized_keys && chmod 600 .ssh/authorized_keys

NOTE: You must make sure that your remote server has ssh installed and running.

Configure Login Shell

We usually do not want the git user to have a normal shell login, so we can set the git user’s shell to git-shell, which restricts the user to only use git commands.

To do this, we first need to check if git-shell is listed in /etc/shells:

# Check if git-shell is already in /etc/shells
cat /etc/shells | grep git-shell
# If it is not listed, we can add it
echo $(which git-shell) | sudo tee -a /etc/shells

Then, we can update the git user’s shell to git-shell:

sudo chsh -s $(which git-shell) git

Forbid Forwarding

We usually want to restrict the git user from performing port forwarding, X11 forwarding, agent forwarding, and pseudo-terminal allocation.

We can do this by modifying the ~/.ssh/authorized_keys file:

# We may need to add the following line to every public key in the authorized_keys file
no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty ssh-rsa AAAAAA...

Upload a Public Key

Now, we need to upload our public key to the git server so that we can connect to it via ssh. We just need to append the content of our local public key to the git user’s ~/.ssh/authorized_keys file.

NOTE: Do not forget to add no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty before the public key in the authorized_keys file.

Create a Remote Bare Repository

Firstly, we need to switch to the git user:

# You may need to enter the `git` user's password,
# or you can switch to the `git` user using `sudo su git`, which will require the `sudo` password
su git

Then, we can create a bare repository named a.git in the home directory of the git user:

# Specifying the path as a bare repository
git init --bare /home/git/a.git

NOTE: A bare repository is a repository that does not have a working directory, which means it only contains a .git directory to store the version control information.

Clone the Remote Repository

If you have completed the above steps, you can now clone the remote repository. Supposing the server’s domain is 1.1.1.1 and the port is 123, the user is git, and the repository path is ~/a.git, we can clone the repository using the following command:

git clone ssh://git@1.1.1.1:123/~/a.git

We can use git remote -v to check the remote repository address after cloning.

We can use the following command to add a remote repository to an existing local repository:

# The `origin` is the name of the remote repository
git remote add origin ssh://git@1.1.1.1:123/~/a.git

Local ~/.ssh/config Configuration

We can simplify the ssh connection by configuring the ~/.ssh/config file on our local machine.

For example, if we want to connect to the git server at 1.1.1.1 on port 123 using the user git, we can add the following configuration to our local ~/.ssh/config file:

Host gitserver
  HostName 1.1.1.1
  User git
  Port 123

After this configuration, we can clone the remote repository using a simpler command:

# No need to specify the `~`, as the `~` is the default path
git clone gitserver:a.git

References

• Git on the Server - Setting Up the Server