I was thinking about setting up an unRaid box but I had a question about it's parity feature and how it works. Suppose I have 6 HDD's all of 3TB each with different data on them. HDD #2 is for DVD rips and #3 is for BluRay rips and I have a bunch of documents spread throughout both hard drives. Now let's say the parity drive is 4TB (the biggest of the array). From what I understand the parity is able to restore any of the drives should any one of them fail so my question is how does the parity take into account all that data spread out from across the drives? If HDD #2 and #3 are 6TB worth of data alone and the parity is only 4TB, how is it that the parity can restore one of those drives (since it has to take into account all the data on all the drives)? If multiple hard drives were to fail how would that work?