I’ve had a home server for years, at first using Windows Server, then Unraid, and now using Ubuntu server. I’ve long known that I should keep a close eye on my spinning rust, but I never really knew the best way to have that monitoring quietly automated in the background, only sending me a message when something bad shows up. If it matters at all (I assume it doesn’t) I am using ZFS on Ubuntu (but not using ZFS as root. It’s mounted in e.g ~/user/storage. My primary drive is an SSD)
What are you all using for hard drive monitoring? What are you using for notifications and (generally) how are you linking those two together?
Have done years of enterprise fault analysis, I promise you that SMART will happily tell you there is a problem at the same time you begin to experience data corruption. You might get lucky and catch and altered sector count spike up, or a temperature value go out of family, but in the field those things really suck at predictions.
If you want to know if a drive is healthy, track data corruption at the file system layer.