A story of storage and suffering

Let me tell you a story of storage and suffering (and also some notes for future self) Several years ago I bought a buffalo NAS, it has/had 4×2TB drives in it. After I got frustrated with the built in OS I forced it to run Debian using Debian_on_Buffalo and foolishly made the main storage pool RAID5. It worked well enough, kinda slow (the CPU was not up to the task of RAID5!) but it worked and…