> You seem to be saying that hardware RAID can’t lose data. You’re ignoring the RAID 5 write hole: > > https://en.wikipedia.org/wiki/RAID#WRITE-HOLE > > If you then bring up battery backups, now you’re adding cost to the system. And then some ~3-5 years later, downtime to swap the battery, and more downtime. And all of that just to work around the RAID write hole. Yes. Furthermore, with the huge capacity disks in use today, rebuilding a RAID 5 array after a disk fails, with all the necessary parity calculations, can take days. RAID 5 is obsolete, and I'm not the only one saying it.