Considering what happened to the Whonnock Server, I would have thought this time around you guys might have gone with a SAN, using ZFS (doesn't have to be ZFS, anything similar also works) which has RAID 6 arrays connected to it to maximise data safety, integrity, prevent bit rot, and avoid a disaster when a raid card dies. I know SUSE Enterprise has a software defined storage solution that is based on Ceph so you can expand storage later by clustering new storinators as you add them. If you want to try this setup. I don't work for SUSE, I have played around with some of their software before and think its really good.
edit: added (doesn't have to be ZFS, anything similar also works)
