Productivity and Security Tipps for SSH. Tips and tricks for a more efficient and more secure usage of ssh(d). We will touch on config file options, crypto settings, 2 factor authentication, ProxyCommands with bastion hosts, server key rotation and much more. SSH (Secure Shell) is a must have tool to remotely connect to servers for administrative purposes or file copying. Most users only use a tiny subset of the features modern OpenSSH versions offer. So will try to demonstrate some of the more ‘obscure’ but often very handy options you may not have looked into, yet.