I found this the other day from Red Hat as I will be soon a proud rentee of a 6 cores/12 threads small power house machine. I believe it’s a concise and easily follow “able” guide that just about any VPS/dedi owner can follows as appropriate for their instrafacture. Without totally losing it in the process…
Combine this with a honeypot setup for automatic bruce forcing bots and I believe this sort of setup can be relatively harden SSH wise that is.