Anyone here have experience with RAID

I'm building myself a PC for xmas, its my first time ever doing so...

basically the motherboard i bought has a built in raid controller that is capable of doing RAID 0,1,5,10

I have 3 1TB hard drives that i want to set up as a RAID 5 array

the problem is that one of the drives is already formatted NTFS with ~900GB on it

first off what would be the best way to approach the situation. Should i take the two empty drives and set them up as a RAID 5 array first. And then add the third disk with data to the array. Then would the raid controller reconfigure the RAID array so that the array now has a final size of 2 TB (n drives minus one for RAID 5) and contain my 900GB of data

or will i need to take the two blank drives set them up as a RAID 5 then copy over my 900GB of data, and then reformat the third disk and add it to the array?

I have no experience with RAID arrays and so I have no clue what to expect.

How do i even go about setting up a RAID array. Would i need to boot into the bios and configure the array there?

LASTly, because of the sheer size of the data in my possession, i was thinking that I should install the operating system onto a separate disk so that if worse comes to worse and i have to reformat/reinstall my operating system, i will be able to do so without needing to backup my data, which i don't have enough external devices to do so....I also expect my data to grow into the upper 1200GB range once i get everything set up. (my college campus has a local peer to peer network in which we all share everything we have...so downloading ~50GB of movies is completely feasible and actually takes ~2 days)

I'm looking for any sort of input here as well as some general help/guidelines

[dunng]

RAID 5 needs 3+ drives so that option is out... Do you have any other spare drives or someone with 900GB to share? OS on another drive is not a bad idea, I do that on most my Servers...

http://en.wikipedia.org/wiki/Redunda...ependent_disks

[RGD.]

I am running RAID 1+0 i.e. 10 with four 500gb drives.

Unfortunately I'm really not going to be much help to you. I did a ton of reading on how to set it up - the problem is finding information on what to do when it goes wrong. I have one bad drive in as much as it's showing an error and degraded.

What I can tell you is that it's highly suggested to run drives of the same size and make, specs.

You will need a floppy drive to install the raid software/drivers - it's most likely on the setup CD that came with your motherboard. When you install your OS it will ask if you need to install third party software or RAID drivers. It's not tough at that point - just install the floppy disk and select which RAID level that you want.

Once you complete the setup you can remove the floppy drive - I didn't mount mine - just left the case open and ran the cable in. I tried it with a USB connection but that didn't work.

Anyway - don't know what else I can tell you - but you can ask anyway.

I plan on later installing four TB drives and starting over.


Ron

the 3 1TB drives that i've got are the same size sector for sector, so I'm not worried about that


I've got two other SATA drives, one is 160GB and the other is 300GB...could i use those to complete my initial raid5 array....also I thought that in order to have the redundancy in RAID 5, you need a third disk. So if i've only got two drives initially there won't be any redundancy <---isn't this what happens when one drive fails anyways?

[dunng]

Yes, but the max that would be used on each is that of the smallest...

Yes, there would be redundancy with RAID 1... the two drives would be Mirrored.

Originally Posted by dunng

Yes, but the max that would be used on each is that of the smallest...

Yes, there would be redundancy with RAID 1... the two drives would be Mirrored.

I was talking about RAID 5, wouldn't it be possible to initially set up the array as RAID 5 without my third disk, and the downside would be no redundancy. Then i can copy my data over and add the third disk

PS: tigerdirect has 1TB hitachi drives on sale for 80$ after rebate

[dunng]

No.

Best bet would be to get the additional drive or borrow space from a friend.

Originally Posted by dunng

No.

Best bet would be to get the additional drive or borrow space from a friend.

well ****

alright, I'll see what I can do, thanks for the help

[spooble]

You can't create a RAID 5 with less than 3 disks. A 2 disk RAID 5 would essentially be RAID 0... Striped with no parity. I think your only option is to backup the data somewhere else, or get a 4th drive. I don't know of any utility that can create a raid array without formatting the drives.

Originally Posted by spooble

You can't create a RAID 5 with less than 3 disks. A 2 disk RAID 5 would essentially be RAID 0... Striped with no parity. I think your only option is to backup the data somewhere else, or get a 4th drive. I don't know of any utility that can create a raid array without formatting the drives.

Thats what i was hoping for, and then by adding a 3rd disk the parity would happen.....BUT i guess things don't work that way

Basically, in my head you can add disks to a raid array without needing to reformat the array correct?, the controller will re-optimize everything itself. Thats what i thought would happen, that by adding a third disk my raid controller would realize that i has room for parity and then it would just work

I'm going to have to end up buying a new HD then, If i combine every hard drive i own and put my data on it, I'd barely reach 700GB and thats on ~5 drives....very risky and inefficient

[feznuk]

Since you already have 900GB of data to deal with I’d buy the additional drive and build the 3-disk raid5 volume with the three new drives. Then you can copy over the data to the new volume.

Remember, there’s a cost for fault tolerance. With three disks you’re going to lose about 1/3 of the total capacity. Your resulting raid5 volume will only be ~2TB.

When finished you’ll have:
- One ~2TB raid5 volume.
- One 1TB non-raid disk.

As far as setting up the array…you should see your raid controller post during bios. You’ll see a banner post with the name of the maker of the chipset (for example, LSI). You usually get some basic information then the controller searches for disks. At some point you’ll be asked to hit Ctrl-H, Ctrl-M (or something similar) to enter the setup utility. That’s where you’ll set up the array.

FYI…you can’t just add a disk to a raid array to change the raid type or number of disks in the array.

[Silound]

I don't quite understand why you need a RAID to begin with.

If all you're doing is sharing large quantities of movies and music over P2P, then there's no reason to have such a complicated storage system. You can simply have 3 large independent drives for storage. if you lose any data, you specifically say that you can download it fairly quickly, so there's no reason to worry about data loss because you can replace it fairly quickly and efficiently.


I would suggest you buy a 10K RPM drive for your OS install and major programs, and use your three larger drives as basic inexpensive storage. Anything you REALLY need to back up, you can burn to a CD/DVD or move to an external smaller drive.

[goalie204]

Anyone here have experience with RAID

oh, not the bug spray? nevermind

Originally Posted by Silound

I don't quite understand why you need a RAID to begin with.

If all you're doing is sharing large quantities of movies and music over P2P, then there's no reason to have such a complicated storage system. You can simply have 3 large independent drives for storage. if you lose any data, you specifically say that you can download it fairly quickly, so there's no reason to worry about data loss because you can replace it fairly quickly and efficiently.


I would suggest you buy a 10K RPM drive for your OS install and major programs, and use your three larger drives as basic inexpensive storage. Anything you REALLY need to back up, you can burn to a CD/DVD or move to an external smaller drive.

Your implying that all 900GB of my data reside somewhere else on the network which isn't true at all, most people pick and chose

I was drawn to RAID because of the big performance boost+the ability to keep a backup at all times

As far as games go, would it be best to install them to my RAID partition so that the game can access its files faster or would it be better to put them on my OS disk?

What DUNNG said...

If you want speed and safety, RAID 0+1... 4 drives... 4 x 1TB will give you 2TB
RAID 5 will give you safety but is actually slower than a 2 drive mirror when writing to the drive because it has to calculate the parity.

You aren't really going to get that much speed gain in RAID 5... A 2 disk mirror will be quicker and a 2 disk striped set will be the quickest but you give up the redundancy...

cheers,
Rudy

Thx guys!

[jquirit]

Originally Posted by MrBucket101

I was drawn to RAID because of the big performance boost+the ability to keep a backup at all times

Please repeat to yourself...

"A RAID array is not a replacement for proper back-ups!"

When dealing with such a small array of drives, all it'll take is for two drives to go dead. And from experience, if you're buying all the drives at the same time, going to be running them all at the same time.. the likelihood of two drives starting to go bad at the same time (ie - one starts going bad, you scramble around to find a replacement to replacement, and in the interim, a second goes bad) is probable. When that happens, there goes your data. Seen it happen before, and I don't want you to share the same fate.

Personally, anything I want to keep I keep on DVD-ROM back-ups. Anything else on the array I can replace with a minimum of discomfort so it's no big loss to me if I lose a drive or two.

Good luck with your project!

[Silound]

Originally Posted by jquirit

Please repeat to yourself...

"A RAID array is not a replacement for proper back-ups!"

When dealing with such a small array of drives, all it'll take is for two drives to go dead. And from experience, if you're buying all the drives at the same time, going to be running them all at the same time.. the likelihood of two drives starting to go bad at the same time (ie - one starts going bad, you scramble around to find a replacement to replacement, and in the interim, a second goes bad) is probable. When that happens, there goes your data. Seen it happen before, and I don't want you to share the same fate.

Personally, anything I want to keep I keep on DVD-ROM back-ups. Anything else on the array I can replace with a minimum of discomfort so it's no big loss to me if I lose a drive or two.

Good luck with your project!

If you're that worried about drive failure, you should be backing up your data regardless. Arrays are NOT a backup, they're a supplement to larger backup methods.

Honestly, arrays are a novelty for the average user. And anything is downloadable on the net somewhere (and if it's truly not, just back it up)

The only thing i can not do without in all of my data, is my personal music collection...which is why its mirrored on 4 different disks, When my last drive failed i only had a partial backup and i was devastated so now i back it up at multiple sources

Thank you all for the help, I've got a WAY better understanding of RAID now, and I may be re-considering the actions i should take.

I think why I'm so adamant for a RAID array is because of the safety net they provide, especially RAID 5, I don't have enough disks to do RAID 0+1, so i figured 5 was a good compromise

I don't think i can really justify backing up all of my data to DVD's, that'd be close to 100 DL DVD's which cost close to 3$ a disc

My data mainly consists of TV shows that I rip from my tuner card and then cut out the commercials so they have a personal attachment to them, and the rest is movies and games and applications that i use from time to time

I can lose all of the data and still survive without it, but to me its nice to have a wide collection of multimedia to choose from when the time strikes

Once again, thanks to everybody for the big help this thread has provided me

[macpappy]

I wish I understood what everyone else said (except about the bug killer).
I was responsible for a server a the printing company I used to work at and ran RAID on it. I had one array linking the drive with the operating system and any software on it to a back up and a second array for the drive that was used as nothing more than an extremely large file cabinet. The operating drive never failed while I was there but the file storage drive did and I was glad we had the set-up that we did. We lost less than 1GB of work and that was easily recoverable.