The way I like to do it is with mirroring of the nvme storage and then lvm snapshots on top of it. Done correctly you get boot off either of them but they're k

The way I like to do it is with mirroring of the nvme storage and then lvm snapshots on top of it. Done correctly you get boot off either of them but they're kept in sync automagically by the OS. then you snapshot the boot volume regularly and copy those to some kind of archival storage for backups. That lets you then even hotswap them if you need to while keeping the root filesystem workable.