What are best practices for using ssh key authentication?

Using SSH key authentication provides a more secure and convenient method for accessing remote servers. Here are some best practices to follow:

• Use Strong Passphrases: Always protect your private keys with strong, unique passphrases to add an extra layer of security.
• Limit Key Access: Only allow specific users and IP addresses in your authorized_keys file to reduce potential attack surfaces.
• Use SSH Agent: Use an SSH agent to manage your keys securely without having to enter your passphrase repeatedly.
• Regularly Rotate Keys: Change your SSH keys periodically to minimize risks associated with compromised keys.
• Disable Root Login: Disable SSH access for the root user in your SSH configuration to prevent unauthorized access.
• Keep Software Updated: Regularly update your SSH server and client software to patch vulnerabilities and improve security features.
• Use Key Types with Strong Algorithms: Prefer using modern key types, such as Ed25519, which are more secure than older types like RSA.