OpenSSH

Coolify uses SSH to connect to your server and deploy your applications. This is true even when using the localhost server where Coolify is running.

Caution

The SSH key must not have a passphrase or 2FA enabled for the root user or the connection will fail.

Configuration Steps

These are the steps to configure OpenSSH for Coolify.

Tip

Normally this is done automatically by the Coolify installation script but in case it is not, you can follow these steps.

1. Install and Enable SSH

   Choose the commands for your Linux distribution:

   Ubuntu/Debian

   sudo apt install openssh-server
   sudo systemctl status sshd

   CentOS/RHEL

   sudo yum install openssh-server
   sudo systemctl status sshd

   Arch Linux

   sudo pacman -S openssh
   sudo systemctl status sshd

   Alpine Linux

   sudo apk add openssh
   sudo rc-service sshd status

   SLES/openSUSE

   sudo zypper install openssh
   sudo systemctl status sshd

2. Configure SSH Settings

   Edit /etc/ssh/sshd_config to ensure these settings:

   PermitRootLogin prohibit-password
   PubkeyAuthentication yes

   You can also set PermitRootLogin to yes, without-password, or prohibit-password (all of these are supported).

   Make sure to restart the SSH service after changing the configuration.

3. Set Up SSH Keys

   If you used the automated Coolify installation script, this step is already done.

   For manual installation:

   # Generate SSH key pair
   ssh-keygen -t ed25519 -a 100 \
       -f /data/coolify/ssh/keys/[email protected] \
       -q -N "" -C root@coolify
   
   # Set correct ownership
   chown 9999 /data/coolify/ssh/keys/[email protected]
   
   # Add public key to authorized_keys
   cat /data/coolify/ssh/keys/[email protected] >> ~/.ssh/authorized_keys
   
   # Set proper permissions
   chmod 600 ~/.ssh/authorized_keys
   chmod 700 ~/.ssh

4. Configure Coolify

   1. Go to Keys & Tokens menu
   2. Navigate to Private Keys section
   3. Add the private key
   4. Set this key in your localhost server settings

Troubleshooting

If you’re having connection issues:

• Verify SSH service is running.
• Check that the right SSH key is set in Coolify.
• Check permissions on ~/.ssh directory and files.
• Ensure the SSH key has no passphrase and no 2FA enabled.
• Confirm you are using the right user.