- Disable pasword auth - https://www.cyberciti.biz/faq/how-to-disable-ssh-password-login-on-linux/
- Create a jump host - https://goteleport.com/blog/ssh-jump-server/
- Authorized keys and permissions - https://superuser.com/a/925859/1863774
- Sudo without password - https://askubuntu.com/a/147265/1098742