[LtStinger]

My initial plan on my wife's new build was not to raid. She's got an SSD, and two 1TB WD Blacks. I was going to give her two different hard drives to play with and the speed of the SSD for programs.

Now when I went in to initialize the drives through windows, I noticed the create mirrored volume and said hmm...I know this is a "fake" raid, but for all purposes she would use this for, I thought, this could be a benefit. What I did was cut a 500GB partition on both 1TB drives, created a mirrored volume between HDD 1 and 2, and left the other two alone, so now she has two 500GB drives to play with, and a place to put family and client's photos to keep them safe in case of a drive failure.

That was my thought anyway. Now I read all about WD and their crappy enterprise marketing BS, and how these don't support RAID, that they drop out of the array, that RAID 1 "is not a backup solution" and I really don't understand why. If I were to take a folder of pictures from my daughter's birthday party and copy them onto a separate drive, I would consider that a backup. Is this mirrored volume not just making this job a little easier for the wife? (Instead of organizing copy/pastes from one drive to another she can just know that anything in this drive letter is safer?)

Since I'm not doing this at a hardware level, since this isn't using the whole drive, and since this isn't containing anything to do with the OS or heavily used files, I'm wondering if this RAID issue with blacks even pertains to me. We're not talking about running an OS in a RAID0 off 4 of these things, just talking about a little partition here for a safe zone...So my real question is this: what exactly is the risk here? Is the risk that the drive will drop out of the array and I will have to enable it again and be fine? Or am I going to lose the data when that happens? Will the drive letter simply go away, or will it split back into two different drive letters until I re-marry them again? Is RAID1 the best option here, I like it but it seems more trouble than it's really worth if it's going to cause problems and not even save data.

I have a hard time understanding why RAID1 is regarded as a terrible option for backing up data against a hard drive failure. If it doesn't do this efficiently, then why would anyone want to run it at all?

 

[DaClownie]

It's not a "terrible" option per se, but it doesn't offer any sort of parity... as in it's not error checking the duplicate to ensure the copy is perfect. For personal use I'm sure it would be more than sufficient, but for any crucial data it's not going to offer you great levels of protection. Perhaps someone with a bit more knowledge can chime in and elaborate if you need it, but that's the short simple version.

If you have pictures or anything of the like that you want to ensure are being backed up, I'd recommend picking up an inexpensive external hard drive, and creating a batch file that writes the picture folder to that, or allowing your wife one 1TB drive to actually store and use, and the other backs up just certain folders that you'd want to keep. Home movies and pictures back up, but mp3 doesn't, for example.

 

[LtStinger]

Right, that's where I'm confused. Why go out and buy an external when I already have sufficient space on my two internals? Why drag certain files over to another hard drive if this is what RAID is already doing for me? In my mind, the way it's set up now, her dragging any files she doesn't want to lose onto the mirrored 500GB partition IS putting those files on both drives. Why would it be any more secure to do this manually with an external?

 

[kevmatic]

The reason that RAID1 is not a backup solution is that it only protects against 1 source of data loss- HD failure. There are plenty of other ways to lose your data: accidental deletion, File system corruption, fire, hardware issues in the computer, etc. RAID1 does not protect against any of those, while a proper backup solution will. That being said, HD failure is probably the number 1 source of data loss, so it helps quite a bit.

Another reason that RAID in general isn't a backup solution is that RAID implementations on hardware controllers differ between controllers, so if the RAID card itself fails, you are s-c-r-e-w-e-d unless you can find the exact same card! This does not apply to software RAIDs: I know from experience you can move a RAID between linux distros, and I've heard you can do the same with Windows RAIDs.

That's why, unless extreme performance is a must, software RAID is actually better than hardware. The linux kernel developers recommend software over hardware RAID in almost all circumstances, so your RAID is not 'fake' at all.

As for why WD doesn't want you to use WD Blacks in a RAID is because they have a more expensive WD Red line that's designated for RAID. The only difference is that the blacks report errors quicker to the OS, while the REDs spend more time trying to fix it internally. This makes the REDs less likely to be "dropped out" of the RAID when its not needed. The drives themselves literally can't tell if they are in a RAID or not.

 

[Sean Webster]

read this: http://www.overclock.net/t/1125994/seans-data-backup-guide
Quote:

RAID is not designed to replace a proper backup solution, it's there to protect against drive failures with minimal to no down time. I don't understand why some people think that just because different RAIDs such as RAID 5 or RAID 6 can take a drive loss and still maintain data integrity that their data is backed up. It simply is not. Data needs to be in multiple places to actually be backed up, not just a single RAID volume in a single PC/location.

RAID arrays do NOT protect against:

• Boot Sector Corruption
• Human error (deleting files by mistake)
• RAID controller/software failure
• Fire, flood, or other calamity such as an EMP in your PC...
• Theft, hacker attack, or other offensive action
• Multiple disk failures and Unrecoverable Read Error
• Data corruption
• Virus'

Simply set up a automated backup routine to the secondary driver rather than RAID 1.

 

[LtStinger]

Quote:

Originally Posted by Sean Webster

read this: http://www.overclock.net/t/1125994/seans-data-backup-guide
Simply set up a automated backup routine to the secondary driver rather than RAID 1.

There's always a better backup solution. If you have three seperate computers with the same data backed up, a fire could hit your whole house. If you upload it to a cloud server, you could lose your account, or they could go out of business, or some other failure on their end. I guess the answer would be to rely on a google cloud storage solution but all those are expensive, and not really required for typical requirements of household pictures we don't want to lose. I don't know. Just trying to make it better and easier, not necessarily fail proof per say.

Quote:

Originally Posted by kevmatic

As for why WD doesn't want you to use WD Blacks in a RAID is because they have a more expensive WD Red line that's designated for RAID. The only difference is that the blacks report errors quicker to the OS, while the REDs spend more time trying to fix it internally. This makes the REDs less likely to be "dropped out" of the RAID when its not needed. The drives themselves literally can't tell if they are in a RAID or not.

This is addressed on a new thread I just made under hard drives, I talked to WD today and they cleared this misinformation up, go read it and input if you know anything to further the research.

 

[Sean Webster]

Quote:

Originally Posted by LtStinger

Quote:

Originally Posted by Sean Webster

read this: http://www.overclock.net/t/1125994/seans-data-backup-guide
Simply set up a automated backup routine to the secondary driver rather than RAID 1.

There's always a better backup solution. If you have three seperate computers with the same data backed up, a fire could hit your whole house. If you upload it to a cloud server, you could lose your account, or they could go out of business, or some other failure on their end. I guess the answer would be to rely on a google cloud storage solution but all those are expensive, and not really required for typical requirements of household pictures we don't want to lose. I don't know. Just trying to make it better and easier, not necessarily fail proof per say.

Or you could delete a file needed a week later but dont have cause you deleted it from the RAID 1 array a week ago.
Or your RAID array could corrupt.
Or your PSU could short.

RAID =/= backup. Better to have data in multiple places rather than one, that is the only way to have a backup.

External drive is the best bet for normal backup as it is portable and you dont have it running 24/7. Just pop it on the PC one a week and run your backup script/task...takes only a few minutes usually.

Otherwise don't listen and have fun with RAID 1 as the only backup solution.