Some SSH advanced features:
- SSH Emergency Access - design a break glass procedure for reaching SSH hosts in an emergency, using security keys that you can store offline
- How to SSH Properly - a few different ways to easily improve the security of the SSH model without needing to deploy a new application or make any huge changes to user experience - certificates, bastion hosts, 2-factor authentication
- SSH Handshake Explained
- gravitational / teleport - from How Uber, Facebook, and Netflix Do SSH
