Setting up SSH Trust Between Two Linux Servers

Establishing SSH Trust Between Two Servers is crucial for secure network connections. This guide will walk you through the process of using SSH keys for authentication, ensuring all user authentication, commands, output, and file transfers are encrypted to protect against network attacks.

Setting up cron jobs for transferring files between servers for backup purposes requires secure authentication. SSH Trust Between Two Servers provides the most secure method by using SSH keys.

To begin creating an SSH key, use OpenSSH, the secure protocol for network administration. Start the process by running ssh-keygen and following the on-screen prompts. Below is an example of generating an RSA key pair.

Generate an RSA key pair by typing the following at a shell prompt:

~]$ ssh-keygen -t rsa 
Generating public/private rsa key pair. Enter file in which to save the key (/home/alex/.ssh/id_rsa):

Press Enter to confirm the default location (that is, ~/.ssh/id_rsa) for the newly created key.

Enter a passphrase, and confirm it by entering it again when prompted. For security, avoid using the same password as your account login. Following these steps, your identification and public key will be saved, as shown below:

Your identification has been saved in /home/alex/.ssh/id_rsa. 
Your public key has been saved in /home/alex/.ssh/id_rsa.pub. 
The key fingerprint is: 
e7:97:c7:e2:0e:f9:0e:4c:d6:d7:cb:e5:31:11:92:14 alex@example.com.
The key's randomart image is: 
+--[ RSA 2048]----+ 
|             E.  | 
|            . .  | 
|             o . | 
|              . .| 
|        S .    . | 
|         + o o ..| 
|          * * +oo| 
|           O +..=| 
|           o*  o.| 
+-----------------+

Next, secure the ~/.ssh/ directory by changing its permissions:

~]$ chmod 700 ~/.ssh

Now to push your key to the remote machine you want to ssh into, type the following command:

~]$ ssh-copy-id remote-user@remote-host

That’s all! Now just try to ssh into the host. You will not be prompted for a password:

~]$ ssh remote-host

By establishing SSH Trust Between Two Servers, you enhance your network’s security, making unauthorized access significantly more difficult. This method not only streamlines the process of connecting to remote servers for file transfers and backups but also fortifies the security of your network infrastructure.