For Hetzner you have to monitor your disks and run RAID-1. As soon as you get the first SMART-Failures you can file a ticket and either replace ASAP or shedule a time. This happened to me a few times in the past years it always has been just 15-30m delay after filing the ticket and at most 5 minutes downtime. You have to get your Linux stuff right through i.e. booting with a new disk.

If you don't like that you can order a KVM-VM with dedicated cores at similiar prices and the problem is not yours anymore.

Most bare metal providers nowadays contact you just like AWS and say "hey your hardware is failing get a new box.". Unless it's something exotic it's usually not long for setup time, and in some cases just like a VM it's online in a minute or two.

thanks!