All my servers are VMs running via Proxmox across 4 physical machines. There is a nightly backup of all servers on NAS-1. There is a weekly backup of all servers on NAS-2. There is a yearly backup of all virtual servers to a Blu-Ray that gets placed in a safety deposit box across town. NAS servers run 4-disk RAID-5. All physical drives run daily SMART tests and send results to Home Assistant and I get instant alerts if one fails.