New
#11
I normally do not advocate RAID for most people but you seem to be an exception to the rule. While I get why you want to keep each type of data on their own drives (I am the same way), it's not the most efficient utilization of your drive space. SSDs are one heck of a lot faster than HDDs for large file transfers but they are not the most cost effective storage medium for large amounts of data; HDDs are the best for that. Also, if you are repeatedly rewriting large chunks of data to an SSD, you could significantly reduce the life of the SSD whereas HDDs are far, far less susceptible to life reduction due to large rewrites.
Using folders in a large single volume (such as can be achieved with RAID 5 or 6 or even JBOD) to keep your various types of files separated instead of using individual drives would reduce the amount of overhead you are now having to allow for each drive since the individual folders can share the same overhead space on the larger volume. Since, right at the moment, 4TB is the largest HDD that is practical right now, you would need a RAID to achieve larger volumes on a single drive letter.
The big issue with RAIDs 5 and 6 or JBOD (spanned drives) is backing them up. While RAID 5 can recover itself when one disk goes down and RAID 6 can survive two disks failing, they are not a true backup because they are still subject to hardware failure (PSU failure, fire, flood, theft, etc.) or file corruption from malware or user error (such as accidental deletion), something many pros have trouble understanding. RAID 0 (mirroring) is also susceptible to the same issues. For a backup to be a true backup, one must have their data stored in two or more completely different places. And 'tis there that RAID creates problems.
Since the volume of a RAID is so large, it would take another RAID to achieve the same volume if one wanted to do a single backup of the entire volume. A NAS would be the easiest way to accomplish that as long as it was actually connected and turned on only during the backup itself.
You hinted at a concern that a failure could occur during a backup (hence, your use of SDDs to reduce the time a backup needs), which is an extremely valid concern. The way to deal with that, of course, is to run more than one consecutive backup. That gets a bit complicated with RAID since all the drives in a RAID have to be kept together but it is doable; just have two or more sets of RAIDed drives and swap them in and out of the NAS when running the backup. You could even keep a set offsite for even more protection from loss.
An even easier way to backup a RAID would be to do file and folder backups with a syncing program. I'm just learning how to do that myself so I can't offer much in the way of details...yet. In a nutshell, however, you would pair up a folder or folders on your computer with an identical folder or folders on a backup drive. You wouldn't have to pair up all the folders on your main volume; only those that will fit on the backup drive. You could then split the entire RAIDed volume amongst multiple smaller drives.
A syncing program, in this case, works by comparing the origin folder with the paired destination folder. Then, it will copy over any new folder/files and replace any changed ones. What you will end up with is essentially an identical copy of the original folder. Since only the new and changed data is being written to the backup drive, fewer writes and rewrites are needed, making the backup much faster (and will reduce SSD degradation). Making multiple backups will be much easier. Also, a syncing program would allow you to use your existing backup drives (RAID sets should always have matched drives). I always recommend a minimum of two backups, one offsite and one onsite, and to update those backups frequently (I'm anal and keep four backup HDDs for each HDD in my computer; that saved my bacon...er...data once).
Something else that would streamline your backups would be to use a dock that connects via e-SATA. While, theoretically, USB 3.0 is almost as fast as SATA III, in actual practice, even SATA II can give USB 3.0 a good run for the money. If your machine doesn't already have an e-SATA port, as long as you have an unused SATA port, you can get PCI covers for the back of the machine that have an e-SATA socket on them and connect the cable from the socket to the unused SATA port.
Last edited by Lady Fitzgerald; 03 Jan 2014 at 01:18. Reason: Clean up typos and cranial flatulence.