My machine as stands had an ASUS P6T SE with 6 x WD 1TB Black Caviar (WD1001FALS-00J7B1)
I ran WDTLER and found that these drives can not have TLER changed in any way. (I am not sure if this relates directly to the problem, but it will sure factor into peoples recommendations for a solution as i have ordered more gear and will not stop until i have the best setup)
I have been running 2 drives in RAID 0 as a striped array for boot partition and another 4 in a RAID 5 array.
The other day during POST the machine claimed that the 5 array was degraded, when i got into the Intel Matrix console it said the drive had failed. I pulled it out and stuck it into another machine did some pretty intense testing from ultimate boot disk and it's fine. I stick it back into the original machine and Matrix gives me an error list saying that 1 of about 8 things "could be wrong" ranging from "the drive is really dead" to "the drive is full" to "the drive is not the same size" etc etc... finally after some hair pulling and massive data transfer to external devices i rebuilt the entire array from scratch... which went fine.
24 hours later its claiming the same drive is dead... i fiddled a bit and managed to convince it the drive was fine and it did a rebuild... 38 hours later the array was/is fine.....
During all of this i have figured 2 things, a) i dont have enough TB and so more is required overall and b) i am not pleased with my setup and want one that is more bulletproof.
I went and ordered a "Sans Digital TowerRAID TR8M-B 8 Bay SATA to eSATA Port Multiplier JBOD/RAID 0, 1, 1+0, 5 Enclosure"
& will be ordering a "HighPoint RocketRAID 2314 PCI-e x4" to replace the 1x PCI-e card that comes with the TR8M
Ok so there i was making my sweet little plan that @ $109.99 the WD Caviar Green 1.5tb are a lot of GB for not so many $
Then i stumbled onto the fact that most new WD Caviar drives are TLER disabled... but for 6 months i have run both RAID 0 and 5 with no problems.... until now...
What are the best drives that i can buy for my TowerRAID, i am so angry with WD for leaving me up a creek here.
Also as a side question that cropped in my mind whilst all this was going on, the RAID on my ASUS P6T SE, is it real hardware raid? or just some software raid? If i find that it is software raid my next question would be, will i get better performance from a controller with propper raid hardware (ROC)
To help people form their opions and much welcomed and appreciated advice, i intend to move forward with either more RAID 5, or just tons of RAID 0 or JBOD and just do my own parity by keeping two copies of everything, depends mostly on what i learn from this thread.
My computer use is mainly as a photographer, working with 15-60mb files and often doing 100gb file transfers from drive to drive or from external drives etc. Also lots of rapid drive reads are required for Adobe Lightroom and of course i use Photoshop also.
If you're using RAID to prevent data loss and if you're NOT doing backups to external media, then you have your priorities wrong. You need external backups to protect against risks to your data that RAID can't safeguard.
With RAID 5, the more disks you use the more at risk your data is. This is because more disks = bigger chance of having one of them fail, and bigger chance of a 2nd drive failure before you can recover.
And don't forget that RAID 5 can only recover if it can successfully read EVERY sector from EVERY OTHER drive. Since hard drives are spec'd to have an unrecoverable read error approximately once in every 10^14 bits read, that gives you something like a 10% chance of being unable to read a sector from a 1TB drive. Multiply that by 4 drives and you're getting uncomfortably close to even odds that your data won't be able to be recovered.
I say all this because (a) when you have a lot of drives then handling drive failures is just going to be a fact of life, (b) therefore you need a well tested procedure for recovering from drive failures instead of thrashing around to see what works while your data is at risk, and (c) IMHO you shouldn't be relying on RAID as the end-all and be-all strategy to protect your data. In fact it may be that eliminating RAID altogether and beefing up your backup and recovery strategy may be a lot simpler in the long run.
sminlal is right, i have briefly used RAID 5 and it's not worth the trouble. In the end, I have and external NAS that has RAID 1 on it and also a separate HDD where I do occasional back-ups from the NAS.
I say the NAS has more chance of hardware-related failure, that's why I use the other external HDD. On the other hand, the NAS is more suited for daily operations, so the external HDD is used only couple times a week. If something happens to the NAS to the extent of not being able to rebuild the RAID, at least I have the external HDD as a back-up to the backup.