OpenSSH Public Key Authentication

Secure SHell is awesome. I think it is one of the most valuable, yet taken for granted tools in Sysadmin's arsenal. This post is about Public Key Authentication, a feature that makes remote access of multiple systems not only faster, but also more secure.

I won't talk about how public keys work. If you don't know it yet, you could learn more here. The point is, I use Public Key Authentication (PKA) very often, on all types of OS, to connect to a large variety of hosts. So here are my preferred ways to set it up.

Making Pageant automatically load keys on startup

So I have a few private keys I generated for Public-Key SSH authentication. In Windows I manage SSH keys with Pageant - an SSH authentication agent for PuTTY. PuTTY is an awesome SSH/Telnet client for Windows that also comes with a suite of helper utilities like key generator and agent.

My work week starts like this: I log into my Windows workstation, open Pageant and load my keys one after another. Since the keys are encrypted I have to enter a password for each key. Once the keys are in memory I can securely log into multitude of Linux servers (that have the public key) without enduring their login prompt each time. Pretty nice, but there is still some room for improvement.