Mastering Proxmox - Third Edition

Node level

Node-level redundancy usually includes redundant power supply, network cards, RAID, and so on. This redundancy is confined to the node itself. With redundant power supply, the node can be connected to two different power sources, thus ensuring continuous operation during power failure.

Always use mirrored SSD drives as the operating system drive. This will ensure that the operating system itself will run uninterrupted, even if a drive fails entirely.