Originally Posted by stanger89 /forum/post/18124744
I don't understand your comments about increasing HDD usage or complexity. If you need 8 drives worth of space, IMO a RAID solution is simpler because you're going to need some sort of controller anyway, and RAID will get you one volume instead of 8.
Drive usage: With a striped array, all
drives must spin to read or write a file. With pseudo-RAID, only the drive where the file resides must spin.
Complexity: Motherboards with 8-10 SATA ports are common. You can easily build a 10 drive server with no additional hardware needed. If you need more, 4-port cards are $20-$30. Compare that to hardware RAID cards which are generally in the $500-$800 range. Both WHS and unRAID allow you to treat all connected drives as one pool, or one volume, if you prefer.
"It is unheard of to lose multiple hard drives simultaneously". RAID or not doesn't change your likelihood of losing multiple drives.
No, but it does change how much
data is lost if you do lose multiple drives. If your hardware RAID array goes down and cannot be rebuilt for any reason
, you lose all data on all drives. Whether you lose multiple drives simultaneously, or faulty hardware corrupts the array, or the controller dies and the replacement just plain won't rebuild for whatever reason, you lose everything. With Hardware RAID, either you have everything, or you have nothing.
With Pseudo-RAID, this is not the case. Nothing is striped, and data is kept whole at the file level. That means that any individual drive can be pulled out of an array, connected to another computer, and the files contained on it can be retrieved. No matter what happens to a Pseudo-RAID array, any drives that are still functional can have their contents recovered. If you have 10 dirves on your server, and suddenly three die, you still have seven drives worth of data. With hardware RAID in that situation, you would have no recoverable data at all.
Originally Posted by ogormask /forum/post/18124761
What else is there?
As others have mentioned, there are pseudo-RAID options like FlexRAID and unRAID. They give you the primary benefits of hardware RAID (drive pooling, parity-based redundancy) without the drawbacks (huge hardware cost, limited upgradability, energy inefficient, potential for catastrophic total data loss). The only thing hardware RAID has over pseudo-RAID is speed. In most cases, unless you need to serve several HD streams simultaneously, this isn't an issue for most home users.