How to set up SSH keys for Plesk server?

Question

How to set up SSH keys for Plesk server?

Answer

1. Connect to the server via SSH.

2. Create the RSA Key Pair:

   # ssh-keygen -t rsa -b 2048

   Use default location /root/.ssh/id_rsa and setup passphrase if required.

3. The public key is now located in /root/.ssh/id_rsa.pub
   The private key (identification) is now located in /root/.ssh/id_rsa file.

   Note: Permissions for the private key should be 0600

4. Copy the public key to another server using the ssh-copy-id command:

   # ssh-copy-id [email protected]

   where user and IP address should be replaced with second server's credentials.

   Note: in case ssh-copy-id is missing on RHEL-based system, use the following command to install required package:

   # yum install openssh-clients

   Alternatively, copy the content of /root/.ssh/id_rsa.pub to /root/.ssh/authorized_keys on the second server.

   Note: permissions for the authorized_keys files should be set to 0600

SSH Keys Manager can be used to upload public part of SSH key pair to a Plesk server.

Additional information

After successful login using the SSH key, it is possible to restrict the password-based login:

1. Open SSH server configuration file:

   # vi /etc/ssh/sshd_config

   2. Find the line that includes PermitRootLogin and set it to:

   PermitRootLogin without-password

2. Apply the changes:

   # service sshd reload