I have about 20TB of data that will remain unchanged (forever) and I am planning to make offline copies with a little redundancy.
I already have a lot of 2TB drives that I plan on using and I am thinking of doing 2TB x3 (RAID 5) arrays with a total of 5 sets i.e. 15 drives with 20TB of redundant data.
Couple of things about my data:
I can also do 2TBx6 Raid-6 with same number of drives and higher redundancy but since these drives will be offline, I do not want more than 3/4 drives per array (most basic servers have 4 HDDs).
My data is reproducible so offsite storage isn't needed and 3-drive RAID-5 is plenty of redundancy.
The data will almost never need to be accessed. Max once or twice in a lifetime. ;)
The data is mostly mp4 archives with huge 3-4 GB files.
Given my requirements, is my planned methodology sane or do I have a better option?