Some help setting up a RAID 1

[Beace]

I'm preparing setting up two drives in a RAID 1 array, and I'm confused about a couple of things.

Using the Intel Rapid Storage BIOS option on my motherboard, I've figured out how to create the array. However, it seems it needs to clear all the data on the drives first, it can't seem to use the data found on 1 drive as master from the start.

I googled to try and find some help, and instead it raised more questions. I found http://download.asrock.com/manual/raid/H67M/IntelRapidStorage/English.pdf which apparantely is a guide for a software version of Intel Rapid Storage. On page 15 I'm getting the impression I might be able to set 1 drive as master if I create the array using the software, so both drives won't have to be cleared. I'm not at all certain about this though, since it lists some requirements that I don't know if my motherboard RAID fills.

Questions:

1) Is it correct that if I create the RAID 1 array using the BIOS, it will have to clear both the drives from data first?

2) What is the difference between using the BIOS and the software options to create my RAID?

3) I'm guessing if I have used the software to create the RAID, and then reinstall Windows a few months later, the RAID will be gone. Will I instead see 2 regular hard drives with identical data on them? Or will the data on the drives be inaccessible?

4) Will I be able to set 1 drive as master and save the data on it to both drives if I use the software to create the RAID?

 

[imabiggles]

1) Is it correct that if I create the RAID 1 array using the BIOS, it will have to clear both the drives from data first?

2) What is the difference between using the BIOS and the software options to create my RAID?

3) I'm guessing if I have used the software to create the RAID, and then reinstall Windows a few months later, the RAID will be gone. Will I instead see 2 regular hard drives with identical data on them? Or will the data on the drives be inaccessible?

4) Will I be able to set 1 drive as master and save the data on it to both drives if I use the software to create the RAID?

A1 - yes
A2 - actually both are really 'software' methods for Raid - true hardware raid controllers are much more expensive. The bios MB method would have less overhead, but only be compatible with that controller. The XP/WIN7 raid options are cross controller compatible but have more overhead/less efficient.
A3 - operating system based RAID is dependent upon the OS, so if windows goes wonky - you're screwed.
A4 - you said you want a RAID 1 array, this question makes me think you do not understand RAID. Two drives in Raid 1 look like one drive. Data is written to both so that if one drive takes a dirt nap, your data/OS (whatever you have on it) is still OK. You can replace the one bad drive and 'rebuild' the array to keep working. Perhaps you should search and read about RAID 0,1,5 array types.

best of luck!

EDIT- whoops, just read the pdf - that intel software monitors the controller and RAID status and helps in setup. Thats not an OS based raid, it is controller based. If you want an OS based RAID - you can look internal windows functions in the disk management service console. Dont think there is a bit of difference if you use the intel software or bios setup version.

 

[Beace]

Thanks for your answers.

A3 - operating system based RAID is dependent upon the OS, so if windows goes wonky - you're screwed.

This answer confuses me a bit, is it based on RAID 0?. If I set 2 drives up in RAID 1, they should be complete mirror images of each other. If 1 drive dies, the other can take over. Shouldn't this mean that if I reinstall Windows, the 2 drives will now show up as regular drives, with identical data on them? And if I want to, I should be able to setup the RAID 1 again, without loosing any of the data (if I go the OS way)?

A4 - you said you want a RAID 1 array, this question makes me think you do not understand RAID. Two drives in Raid 1 look like one drive. Data is written to both so that if one drive takes a dirt nap, your data/OS (whatever you have on it) is still OK. You can replace the one bad drive and 'rebuild' the array to keep working. Perhaps you should search and read about RAID 0,1,5 array types.

I do understand it, what I really meant was that when the RAID 1 is created in the OS, it will treat my current hard drive as a sort of "temporary data master", and mirror all the data from it to the second drive. After that creation part is done, I'd expect it to work like you describe. I've done some more research, and found http://www.overclockers.com/setting-up-os-raid-with-windows-7-ultimate/, which shows that when using the OS you won't have to lose any data when creating the array.


A new question: If I were to set up my RAID 1 with the BIOS on 2 SATA ports, would it then be completely screwed up if I changed to 2 other ports at a later date? Or is it smart enough to see it's the same drives on different ports, and it'd go on without any hickups? (I got a Sandy Bridge motherboard, and plan on switching the RAID drives from the 6Gbit ports to the 3Gbit ports when I get a replacement motherboard)

 

[Beace]

EDIT- whoops, just read the pdf - that intel software monitors the controller and RAID status and helps in setup. Thats not an OS based raid, it is controller based. If you want an OS based RAID - you can look internal windows functions in the disk management service console. Dont think there is a bit of difference if you use the intel software or bios setup version.

Ah, that makes some things more clear to me. Thanks.

 

[imabiggles]

K - I think we are straight on OS RAID = special windows/other OS based disk stuff, nothing to do with what you want done.

If you have a windows install on drive X and now want a raid 1 array to include your OS install - you setup either in BIOS or that tool a new raid array with two new drives - clone your OS drive over to the array, disconnect the old drive, change bios to boot from new array, and Bob's your uncle.

You need to make sure RAID is enabled in bios for the controller you are hooking up the new drives to. There could be software out that might allow you to use your existing drive in a new array - essentially rebuilding an array from current install - but that is a recipe for disaster I think. You can use whatever ports you like on the array as long as it is on the same controller. The controllers bios will detect the array. You will only be screwed if you move the array to a different controller that is not backwards compatable to the one you current have. IE if you motherboard takes a dump. I do not use RAID as a substitute for a good backup set.

 

[Beace]

Well, I've been fooling around with this for a while now. This is my experience:

I started with installing Intel Rapid Storage to try to set up the array through the motherboard option. I couldn't get it working, didn't get any options to actually create a RAID even though I had changed from AHCI to RAID in the BIOS. Doesn't matter, I had done some more reading and most people recommend staying away from the motherboard solution. Just doesn't work well. I didn't make any effort into making it work, but rather moved on to try an OS RAID set up through Windows Disk Manager.

It went very easy. I simply converted to dynamic disks, and then choose "Add mirror" on my main drive. Took like 10 hours for the drives to synch, but I could use the computer normally while it took place, and after things were fine. I let things be for about a day, seeing that things seemed to work normally, which they did. Then I decided to simulate a disk failure, and disconnected the power cable to one of the two drives in the array with the computer still running. I was still able to access the volume, so the mirroring was really working. However, after this it was all trouble.

First of all, I did not get any kind of error message. The only sign of a disk failure was a yellow symbol and some text in Windows Disk Management. Far as I could tell, I could go on for months not having a clue one drive was no longer properly connected. This is my main issue.

Second thing that happened was after I did a shutdown and reconnected the hard drive. Windows would no longer recognize the mirror array, nor any of the related drives. After some clicking around in Windows Disk Management, I managed to get the drives working correctly again, but the array was gone and dead. I simply had 2 drives with identical data on them. I could of course rebuild the array, with another 10 hours of synching. Furthermore, some googling on the issue showed that this isn't even very uncommon, and it can happen after you've disconnected the drive with the computer shut off, or after a BSOD.

Simply put, even though I didn't lose any data in my simulated drive failure, I was left not trusting the whole concept. Which was the whole idea from the start, to feel my data was safe and secure (as far as can be expected anyway) without having to give a second thought to it.

Now, I've decided to simply get some backup/synching software that'll synch all the data from the "main drive" to the "backup drive" like once a week or something. Not as elegant and carefree as I had hoped, but at least it should be reliable.