Gigabyte Raid5 set up

[RaidProblemGuy]

My motherboard is: Gigabyte ga-890fxa-ud5, which has a built in raid controller. I have been running a single 1TB hard drive with windows 7 on it but recently purchased three Western Digital WD Black WD1002FAEX 1TB HDDs since I wanted to set up a RAID5.

So two days ago I plugged in these three drives, and went through the Gigabyte bios and built in raid config, setting up a RAID5 for them. I then logged into my operating system and did a format and configured the new 2TB logical drive to use in my OS. I started putting files onto it and everything seemed to work great, as far as I could tell.

However, today for the first time I rebooted, and the hardware raid controller provided by Gigabyte cannot detect one of the drives. When booting I see
1. The bios, detecting 1 IDE device which is my original OS hard drive
2. The Raid? screen, which says "scanning for drives" and then says my Raid status is critical because it cannot find one of the drives
3. My OS loads

All my drives are visible in the bios, and even the motherboard raid config screen shows the drive is healthy, but viewing the RAID I set up shows that one of the drives as disconnected/missing. I made sure that the drive was plugged in properly, and the BIOS reads it, so I'm not sure why the Gigabyte built in motherboard raid config can't find the drive anymore, although it was the first time I rebooted.

Some interesting things,
-Windows still sees the 2 TB drive that it say a few days ago, and I can pull files off of it, but now there is a new unformatted unconfigred 1 TB "Local Disk ( E: )" showing up.
-The bios sees the 1 IDE hard drive, then a SCSI 0 MyRaidName and a SCSI 1 Hard Drive, which seems similar to what windows sees.

Some tech specs:
Motherboard Model: GA-890FXA-UD5(rev. 2.0)
* BIOS Ver : F2
CPU Brand : AMD
Operation System : Win 7 64-bit
Power Supply : 850 W
HDDs: Western Digital WD Black WD1002FAEX 1TB (times 4, 1 OS and 3 RAID5)

 

[dingo07]

your post loses me when you indicate "did a format and configured the new 2TB logical drive to use in my OS"

if you have 3 1TB drives, where do u get a 2TB logical drive from???

u already had the OS installed on a drive - u should've left that alone, and only installed the 3 new drives to setup for the RAID 5

remove the new drives, put the original drive back where it was and boot from it like normal, remove any indication of a RAID Array in the controller

then install the 3 new drives and create a new Array, then boot into windows and create the 3TB Volume

and u need to use GPT also... http://msdn.microsoft.com/en-us/library/windows/hardware/gg463525.aspx

 

[RaidProblemGuy]

Sorry I should clarify. I set up the raid through a BIOS raid controller, provided by Gigabyte. Through the bios settings I was able to designate my first four sata ports as RAID ports (where I plugged in my three new drives) and then my last two to be normal IDE ports (where I connected my OS drive, since I didn't want it to be a part of the raid). Since the RAID wasn't handled at all by Windows, all windows sees is a simple 2 TB drive that's been plugged in and needs to be formatted/have a drive letter assigned to it.

The reason for the 3TB -> 2TB is that the RAID 5 standard uses an entire drive's worth of space for the parity bits.
http://en.wikipedia.org/wiki/RAID#Standard_levels

 

[ss202sl]

Is there anything on the Raid 5 drives? What happens if you move the raid drives around, and re-create the raid? Does the missing drive in the bios move with the drive?

 

[RaidProblemGuy]

I used a different power connector, and a brand new SATA3 cable I had extra. I know exactly which HDD is not being correctly associated through unplugging each drive and rebooting deduction, and so after I figured that out I moved the non-associating drive to different ports and the problem persists.

What I haven't done is wipe the drive, kill the RAID, and recreate the RAID yet. When everything was working yesterday I moved half a TB to the RAID and haven't had time to move everything out yet, I don't want to lose any of that data by destroying/recreating the RAID. I will of course move everything back to my main drive and do that, but I was hoping someone might know what's wrong because I would just set it up the same way and may end up right back where I am now.

 

[dingo07]

honestly... I wouldn't even recommend setting up a RAID 5 without 5 drives. 3 drives are data, one drive is allocated as the Hot Spare, and the last drive is a failsafe for when one drive dies.

If you lose a drive now, you're sol

 

[noidea_77]

Let's try a summary here:
- raid5 with three drives is ok. Only keep in mind, that you need an exact or bigger spare drive, if one of the original ones fails
- 2TB logical drive are the result of two 1TB data drives plus 1TB parity drive. That's how raid5 works

Back to you problem:
- it's not really a hardware raid 5! It's in fact a software raid. The parity math is done by the CPU via the driver
- what the bios does is writing the raid information to the MBR. The MBR on one of the drives seams to be faulty now and the disk is now longer been recognized as part of the raid set.
- to fix your raid array, read the manual under "Rebuilding an Array". It tells you how to add the third drive as a spare drive to the array and start the rebuild. Rebuilding the array will take very long!
- lessons learned: it will happen again! mobo raid5 is unstable and does not replace a backup.

 

[RaidProblemGuy]

Wow first off thank you to everyone, I've often found great threads on tom's hardware from google, but I've never made an account and didn't realize how great this community was, thanks!

Now back to me problem (haha), I think you hit the crux of the problem when you mentioned the MBR, I'm guessing that when I configured the drive to work in windows, I must've overwritten/messed with the MBR on one of the drives, since I bet windows wrote to the mbr of the "drive" which really ended up just being the MBR of one of the drives, the one that's now not associating correctly.
So this brings me to this lesson, and makes me feel bad for not doing my homework. What kind of RAID5 set up should I use as opposed to mobo RAID5? I figured the closer it was to the hardware, the faster and better it'd run, but really at the end of the day what I want is data integrity, I of course will keep all vital data backed up but the large portions of it I would like to be salvagable in the event that one drive goes down. Would a raid card be a better option? Or just using Win7 raid?

At this point I'll back up the data I have on the drives currently, and then recreate the raid, but my new question is, how should I recreate the RAID to accomplish my goal of data integrity? Are there any good sources I could read on how to accomplish such a set up?

Thanks again noidea_77, you had some great ideas.

 

[noidea_77]

What you want, is exactly what i wanted for my data and i ended up with a NAS box (or two in fact, one for backup only). I fiddled around with some configurations with local disks. The only way to get that reliable is a real hardware raid with a adaptec or LSI controller, but those supporting hardware raid5 are expensive. Every other local solution is always a software raid and crashes with your os and the drivers. Imagine you mobo gets faulty in the future and you have to by one with the exact same chipset, only to get your raid5 data back. The NAS boxes use software raid also, but there hardware is specially designed for that and you get a linux os with it that is customized for this hardware and reliability. I've two Thecus boxes for years now and never lost any data.