Chapter 10: Secure remote access

Log in to other machines safely with SSH, authenticate with keys, move files between hosts, and harden the SSH server without locking yourself out.

What you will learn

• Connect with ssh, verify host keys, and handle a changed key correctly.
• Create a key pair, install it with ssh-copy-id, and fix permission problems that block key logins.
• Copy files with scp, sftp and rsync, and define host aliases in ~/.ssh/config.
• Configure sshd through drop-ins, check it with sshd -t and sshd -T, and change it safely.

Sections

1. Logging in to other machines with SSH
2. Exercise: Verify a server's identity
3. Key-based authentication
4. Exercise: Passwordless access for an account
5. Copying files and saving connection settings
6. Exercise: Move files between machines
7. Configuring and hardening the SSH server
8. Exercise: Harden sshd, safely
9. Exercise: Secure remote access review
10. SSH quiz
11. SSH cheat sheet