# RAID spontaneously degrading (Intel RST)



## Violet_Shift (Oct 1, 2015)

Hello everyone.

I'm having a few problems with my RAID, and given that this is the second time this has happened I feel I'd rather ask for help rather than blindly go replacing disks.

Last night while I was playing a game (loading from the RAID), the game froze and crashed, and RST gave me an alert saying that an error occurred. When I restarted the PC, RST tells me it's rebuilding.

Once the rebuild was done all seemed fine until the next day when I started the computer it reported the RAID as  in "Rebuild" state and I go through that again... only to have RST again decide to rebuild the blasted thing less than an hour ago.

This first happened a few months ago, and in the end I replaced the disk in question to spare myself the aggravation. Seems it was only a stop-gap solution!

The thing is it doesn't seem there's anything wrong with the disks that "failed". They work perfectly fine up until RST decides it's rebuild time again.

I'm using a RAID-5 with four 3TB disks. Terrified to even use the computer now, given that I'm one spontaneous "disconnect" away from losing 4+ terabytes of data. (and given that I'm in the mood for gaming for the first time in a while!)

I really am a noob at this so if anyone wants to help me and anything complicated is involved can they please take it slowly with me


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## Assimilator (Oct 1, 2015)

First principles: do you have the latest version of Intel RST installed? The latest as of this writing is 14.6.0.1029 - download and run the SetupRST.exe executable from here.

Secondly, are all the disks you're using from the same manufacturer and model? Mismatched disks can give very subtle and difficult-to-solve problems.

Next, are the disks you're using certified by the manufacturer for use in RAID volumes? Some disks, particularly the "Green" models, aren't suitable for use in RAID because they behave in a manner that the RAID controller doesn't expect. For example, if a Green disk goes into power-saving mode, and the RAID controller tries to read from it, the Green disk may fail to wake up fast enough to read that data, and the controller will assume this is because the disk is going bad. If this happens enough times, the controller will drop the disk from the array.

Double-check the SATA power and data cables. If possible, try swapping them for cables you are certain are good. I have personally experienced an issue with a bad data cable that didn't affect the data on the drive, but did make the RAID controller very upset. If it's always the same drive that seem to go "bad", that's a strong indicator that that drive's cables are actually the problem.

If none of the above are helpful/relevant, the disks may not be working as well as you expect. Install a SMART monitoring tool like Hard Disk Sentinel to check and verify your disks' health.

Should SMART show that your disks are all good, it doesn't mean you're out of the woods. Hard disks have a nasty habit of claiming they're working perfectly, up until they day they fail. At this point I would recommend getting hold of your disk manufacturer's low-level diagnostic utility (e.g. Seagate's SeaTools) and running it against your drives. If those utilities find a drive defect, they will generally guide you through the process to RMA the drive.


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## FordGT90Concept (Oct 1, 2015)

RST should provide the serial number and model of the hard drive that failed/caused degradation.  If it doesn't/isn't, I'd consider replacing the SATA cables and see if it still does it.


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## brandonwh64 (Oct 1, 2015)

Same thing happened to my new SSD raid 0 setup. It worked fine for about a week then I booted up and the bios raid screen shows "error occurred" but it still booted into windows then RST showed that one drive had failed. Its kinda odd that if a drive was failed that it would not boot into windows since its a raid 0 stripe but I could be wrong.


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## Athlon2K15 (Oct 1, 2015)

Id suggest if you are going to dabble with RAID use hardware RAID and not the intel onboard shit.  Only thing you can really do is get your data off those drives before RST throws a fit, possibly changing SATA cables like FORD said above.


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## brandonwh64 (Oct 1, 2015)

I am actually pulling my second SSD and I installed a 4TB hard drive for storage/game install.


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## Disparia (Oct 1, 2015)

Which drives Violet_Shift? There may be updated firmware available for them.

Awhile back I had some Seagates that didn't get along with each other but after checking their site I found a new firmware that fixed a reporting bug. They got along after that, six of them in RAID-5.


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## AsRock (Oct 1, 2015)

Disks should be the same for best performance with raid all so it only takes one to spin out of order to make it fail.


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## Violet_Shift (Oct 1, 2015)

Yeah, the disks are all standard Seagate disks (model ST3000DM001, although the newer one has a different suffix after the model number - this is not the currently misbehaving disk however).

I might nab replacement SATA cables this weekend (just in case) and see if I can swap the questionable drive over to another power cable. 

Tried to download HD Sentinel but it keeps failing sadly. I've never noticed any SMART warnings at BIOS or anything though.

SeaTools came up clean.


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## Disparia (Oct 1, 2015)

Violet_Shift said:


> Yeah, the disks are all standard Seagate disks (model ST3000DM001, although the newer one has a different suffix after the model number - this is not the currently misbehaving disk however).
> 
> I might nab replacement SATA cables this weekend (just in case) and see if I can swap the questionable drive over to another power cable.
> 
> ...



http://ask.adaptec.com/app/answers/...with-seagate-barracuda-7200.14-desktop-drives


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## Violet_Shift (Oct 1, 2015)

Jizzler said:


> http://ask.adaptec.com/app/answers/...with-seagate-barracuda-7200.14-desktop-drives



Thanks a lot!

On the EXE version of the firmware updater it says "Don't use on a RAID". Is it safe to use the ISO version on a RAID without wiping all of my data? I'll back up the really important stuff but there's a mountain of stuff I don't have the space elsewhere to keep.


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## FordGT90Concept (Oct 1, 2015)

I wouldn't mess with the firmware without having a backup first.  The drives should be removed from the RAID before updating the firmware and then reintroduced to the RAID.

If all of the errors are stemming from one drive, I'd be thinking about replacing it.

You could test the cable by swapping the cable with a non-failing drive and see if the failing follows the cable.  Only do this when the RAID is normal.  If it degrades on two drives simultaneously, you could risk losing data.

Intel RST can degrade a RAID if the computer shutdown was interrupted.  Check the system event logs for warnings/errors, especially those related to an unexpected shutdown.


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## Disparia (Oct 1, 2015)

Violet_Shift said:


> Thanks a lot!
> 
> On the EXE version of the firmware updater it says "Don't use on a RAID". Is it safe to use the ISO version on a RAID without wiping all of my data? I'll back up the really important stuff but there's a mountain of stuff I don't have the space elsewhere to keep.



That's how I did it with the 7200.11s in my other post. Created a bootable CD using the ISO (will also work with USB stick), booted from it, and applied the new firmware to all drives. I probably had to switch from RAID mode to AHCI (or IDE) in the system BIOS for the drives to show up in the updater. After the update need to switch back from AHCI to RAID of course.

I just "did it" because I noticed a problem during the OS install (bad performance) so there was no data to lose if something went wrong. If you can't backup everything you can't live without, work on that issue first.


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## Violet_Shift (Oct 1, 2015)

Oh, I can back up mission critical stuff of course. And I have, and am doing an up to the minute one now as a precaution. I'm more thinking of the "stuff I have that would annoy me to lose" category, such as my music library and my Steam installs (limited download caps are fun).

I'll wait for the rebuild to finish (currently at 80%), shut the PC down, remove the offending drive, plug it into another machine, update firmware, and reintroduce it. If that lasts long enough without any issues I'll repeat the cycle with the remaining 2 drives using the old fw.


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## Aquinus (Oct 1, 2015)

Drives without TLER like the 4x1TB WD Blacks in my RAID-5 paired with having Patrol Read enabled would spontaneously cause my array to degrade on random occasions. If the connection between the south bridge and the CPU is finicky (such as from an overclock,) it might cause an error as well. My RAID does occasionally rebuild/verify my array automatically. I do think RST occasionally confirms that the data is correct (since parity data enables you to not only re-create data but, verify that it's correct,) but it doesn't tend to go to a degraded state when this occurs since it's corrects errors if either the actual data or parity data is correct.

A loose or defective SATA cable could cause issues like this as well. I would suspect this if it's always the same drive causing the error.


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## Static~Charge (Oct 1, 2015)

Violet_Shift said:


> Tried to download HD Sentinel but it keeps failing sadly. I've never noticed any SMART warnings at BIOS or anything though.



Alternative:

CrystalDiskInfo
http://crystalmark.info/software/CrystalDiskInfo/index-e.html

Download the portable version.
Unzip the file.
Run the appropriate executable: standard (32-bit) or X64.


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## Violet_Shift (Oct 1, 2015)

I ran CrystalDiskInfo and it's saying 3 of the 4 drives are OK. Curiously the drive that's been misbehaving (in the number 4 slot) is OK, and it says the slot 1 disk is "Caution". I don't understand how to read this or if I should be replacing this disk.


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## FordGT90Concept (Oct 1, 2015)

It's the serial number that matters.  What does RST say about Z1F0YM7D? Was Z1F0YM7D the one that fell out of the array?


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## Violet_Shift (Oct 1, 2015)

No, it wasn't. Z1F0YM7D is on port 0 according to RST, and it's the port 3 disk that fell out. Although now I'm worried that I have two malfunctioning disks on my hands.


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## Violet_Shift (Oct 1, 2015)

So I just read a few articles saying that the ST3000DM001 is a particularly awful drive with a high fail rate and a bunch of other bad things. Tempted to just clone the array to a single drive from a more reliable provider and run away screaming from Seagate. Glad that I saw this before disaster struck though.


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## Assimilator (Oct 1, 2015)

Heh, if you'd said up front you were using ST3000DM001s I would've told you to run. Glad you figured it out though.


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## Violet_Shift (Oct 1, 2015)

Thanks. If I hadn't came here I wouldn't have figured this out.

I think I'll get a WD 4TB and dump everything on there, and use this RAID until it dies to run games off. Will be curious to see how much longer it lasts after I've flashed the firmware.


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## AsRock (Oct 1, 2015)

Because it's falling out of raid don't mean the drive is failing, it just means it's not keeping in sync with the other drives which as i said you should keep a raid all the same drives then this is less likely to happen.


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## Violet_Shift (Oct 1, 2015)

Hence why I'm not in panic mode yet. I'm backing up important things to drives that are lying around not in use, and I'll replace the cables and flash the fw tomorrow. I'll report back after that.


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## Aquinus (Oct 2, 2015)

Violet_Shift said:


> I ran CrystalDiskInfo and it's saying 3 of the 4 drives are OK. Curiously the drive that's been misbehaving (in the number 4 slot) is OK, and it says the slot 1 disk is "Caution". I don't understand how to read this or if I should be replacing this disk.View attachment 68286


CrystalDiskInfo does a piss poor job at reading SMART information. Could you use GSmartControl and let us know what it reads for those two fields? If the raw data is simply a hex value, you have 84 uncorrectable sectors, GSmartControl should confirm that. That could be the reason for the RAID becoming degraded.

You can get GSmartControl here.

I highly recommend this tool because it can detect through most RAID setups, properly detects raw values for SMART attributes, and allows you to view and run SMART diagnostic tests.

I personally think that this is the best GUI tool for this task.


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## Violet_Shift (Oct 2, 2015)

Had a look at GSmartControl's output on that particular disk.

Here are the results, but I think I can interpret this myself.

The rest of the drives except this one have nothing listed as suspect. (No errors, etc). The most recent of these errors, according to the time logged, was 6 hours ago - probably while I've been copying hundreds of gigabytes of stuff on to other drives to save it.

Could this drive's behaviour also have been responsible for the "failure" six months ago that showed identical symptoms? I replaced that disk but maybe it's actually OK and this is the one that I have to worry about.


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## Aquinus (Oct 2, 2015)

Violet_Shift said:


> Had a look at GSmartControl's output on that particular disk.
> 
> Here are the results, but I think I can interpret this myself.
> 
> ...


All of the errors being within the same hour is interesting. I recommend running an extended SMART diagnostic test. If it generates an error, you probably have a drive that's on its way out.


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## FordGT90Concept (Oct 2, 2015)

Still odd that the drive with SMART errors isn't the one that fell out of the RAID.


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## Aquinus (Oct 2, 2015)

FordGT90Concept said:


> Still odd that the drive with SMART errors isn't the one that fell out of the RAID.


Then run extended tests on all the drives. That behavior sounds like no TLER and patrol read enabled. It's probably timing out when trying to recover a block and takes too long. Also keep in mind this drive is only throwing errors because blocks are non-correctable. The other drive might be correcting the blocks but, it may be timing out because of no TLER.

The OP should check SMART attribute IDs 5, 197, and 198 on the other drives as well.


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## Violet_Shift (Oct 2, 2015)

Right, running extended self tests on all four drives.

The one I just showed the errors from failed immediately and is telling me "Completed with read failure". I'm removing this one from the RAID as soon as I can and tossing in the old "failed" one to see if that one is an innocent victim in all of this once all the self-tests are done, assuming there's nothing wrong with the other three.

All I know at this point is that I'm never touching another Seagate product again. I've used WD all the time before I built this RAID (sadly in the aftermath of the whole Thailand thing)  and I never had a problem.


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## Slizzo (Oct 2, 2015)

Yeah, I have a hard time looking at replacement drives for my old 1.5TB WD green. The cheap drive is always the Seagate. May go with a Toshiba or HGST eventually.  WD Blacks are just too expensive now IMO.


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## FordGT90Concept (Oct 2, 2015)

It depends on the model more than the brand.  All hard drives are not created equal.


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## Violet_Shift (Oct 2, 2015)

Yeah, it seems that the 4 tera Seagate drives have better failure rates. Sadly I don't have the $ to replace the whole array at this point so I'm praying that the one that "failed" 6 months ago is okay. I'll test it once all this is done. At 50% on the extended self-tests.


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## FordGT90Concept (Oct 2, 2015)

I'm pretty sure Intel RST doesn't consider "caution" a failed state.  It runs the drives until SMART switches to "failed."  Don't get me wrong, the drive should be replaced but I'm not confident it will fix the RAID degrading.


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## Violet_Shift (Oct 2, 2015)

Next step is the firmware update then (maybe that's why they're dropping?). Still waiting on the extended surface scans to finish.

I had a look at the SMART status as the old drive that fell out of RAID six months ago and it has the same problems on it.


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## Violet_Shift (Oct 3, 2015)

I decided to upgrade the firmware on the drives now, but I've ran into (I think) a minor problem. I executed the upgrade, and it seems to be done, but the program isn't prompting me to do anything.

The guide online told me to turn the computer off when prompted but it's been a few hours with the screen never changing and I've received no such prompt:
 

Already probably lost my data from doing this (fortunately backed up, still the frustration factor) but I really don't want to wreck the 3 good drives. Anyone know what to do next? Am I good to turn the machine off?


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## FordGT90Concept (Oct 3, 2015)

It looks done to me.

Z1F10KGX CC4B -> CC4H
Z1F10BAH CC4B -> CC4H
W1F4TWMN CC29 -> skipped
Z1F0YM7D CC4B -> CC4H

The three that the firmware applied to were updated.


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## Violet_Shift (Oct 5, 2015)

Thanks. I was just a bit paranoid. Always am when it comes to firmware.

Anyway, after a few days I've not had any problems, so I presume the firmware update corrected the problems. 

Now there's still the question of the suspect hard drive which I do want to replace before it causes any problems, but I'm very hesitant to buy another ST3000DM001.

If I progressively replace them with the WD Black WD3003FZEX drives (one at a time with a rebuild after each of course), will I be ok? They have the same capacity, interface, and spin rate, but I am concerned about mixing drives regardless.


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## Solaris17 (Oct 5, 2015)

Aquinus said:


> CrystalDiskInfo does a piss poor job at reading SMART information. Could you use GSmartControl and let us know what it reads for those two fields? If the raw data is simply a hex value, you have 84 uncorrectable sectors, GSmartControl should confirm that. That could be the reason for the RAID becoming degraded.
> 
> You can get GSmartControl here.
> 
> ...



I dont gsmart fucks up SMART reads on SSDs all the time at work I recommend CDI


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## FordGT90Concept (Oct 5, 2015)

Personally, I'd just buy a hard drive with a 3+ year warranty and put it on the shelf until Intel RST kicks the drive out of the RAID.  Then I'd swap it.

Yeah, of course you'll be okay.  RAID has the best performance using identical drives but we're talking a very tiny difference in performance.  It's actually better to have a variety of drives because then you're less likely to lose two drives simultaneously which, on RAID5, is fatal.


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## Aquinus (Oct 5, 2015)

Solaris17 said:


> I dont gsmart fucks up SMART reads on SSDs all the time at work I recommend CDI


Could you explain that in a little more detail? Do you mean it gets the attribute names wrong or that it screws with actually reads from SSDs? CDI sucks because it doesn't tend to read values properly which leaves you to trying to interpret the raw data. I've also had no issues using smartmontools (the library under gsmartcontrol,) on several SSDs.


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## Solaris17 (Oct 5, 2015)

Aquinus said:


> Could you explain that in a little more detail? Do you mean it gets the attribute names wrong or that it screws with actually reads from SSDs? CDI sucks because it doesn't tend to read values properly which leaves you to trying to interpret the raw data. I've also had no issues using smartmontools (the library under gsmartcontrol,) on several SSDs.



I've never had issues with CDIs attribute reads. I have however had GSMART tell me drives are fine when they are clearly failing no boots, system disk missing lock up on data access R/W but CDI would display the issues clear as day.


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## FordGT90Concept (Oct 5, 2015)

For the record, SeaTools is going to be the best way to test Seagate drives for failures.  If you're thinking RMA, you need the number it generates anyway.  They have to be removed from the RAID for SeaTools to detect it though (at least last time I tried).


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## Aquinus (Oct 5, 2015)

Solaris17 said:


> I have however had GSMART tell me drives are fine when they are clearly failing no boots, system disk missing lock up on data access R/W but CDI would display the issues clear as day.


What in particular would that be that CDI saw that GSC didn't? I find that GSC gives more information than CDI, not less. It's nice being able to check the SMART error log and the results of SMART diagnostic runs though, I don't recall CDI being able to access much beyond the attributes themselves.

Also consider what the OP saw with it. It's clear as a sunny day that he has at least 1 drive with issues. All of those errors happened within hours of the OP sending the screenshot.


Violet_Shift said:


>


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## Solaris17 (Oct 6, 2015)

Aquinus said:


> What in particular would that be that CDI saw that GSC didn't? I find that GSC gives more information than CDI, not less. It's nice being able to check the SMART error log and the results of SMART diagnostic runs though, I don't recall CDI being able to access much beyond the attributes themselves.
> 
> Also consider what the OP saw with it. It's clear as a sunny day that he has at least 1 drive with issues. All of those errors happened within hours of the OP sending the screenshot.



I don't really need to consider anything about what the OP said. I guess i'm not really understanding why you are attempting to argue? Gsmart hasn't worked correctly on hundreds of drives (I literally analyze thousands a year) Attributes specifically wrong on gsmart are the wear attribute indicator and bad/pending sector count. 



> What in particular would that be that CDI saw that GSC didn't?



huh? 



> I have however had GSMART tell me drives are fine when they are clearly failing no boots, system disk missing lock up on data access R/W but CDI would display the issues clear as day.



just going to nip that before it becomes a problem. I suppose im just going to attempt to make it clear that im after the CORRECT information. I could care less if CDI was missing something like the short test etc.


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## brandonwh64 (Oct 6, 2015)

This is what mine looks like but the its still fully functional and only real issue I see is that speeds are around 550-600MB instead of 1000+ as they where when I first set it up.


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## FordGT90Concept (Oct 6, 2015)

When you click on the drive that has the exclamation point, what does it say?  Since it is an SSD, I suspect that ! drive went into read-only mode which is why it is 550 MB/s now but the RAID0 is still functional (the non-failed drive is accepting all the writes).


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## Aquinus (Oct 6, 2015)

Solaris17 said:


> I don't really need to consider anything about what the OP said. I guess i'm not really understanding why you are attempting to argue? Gsmart hasn't worked correctly on hundreds of drives (I literally analyze thousands a year) Attributes specifically wrong on gsmart are the wear attribute indicator and bad/pending sector count.
> 
> huh?
> 
> just going to nip that before it becomes a problem. I suppose im just going to attempt to make it clear that im after the CORRECT information. I could care less if CDI was missing something like the short test etc.


I've found issues with drives causing occasional issues by using the extended test, I wouldn't call that worthless. Also considering these tests can be run independently of the OS is a plus. The error log also is incredibly useful and the usefulness is shown in the OP's screenshots. I agree that the GSmartControl isn't ideal for reading SSDs, but what is the OP diagnosing again? The problem is that SMART isn't consistent across vendors but tends to be more consistent with HDDs as opposed to SSDs. According to GSmartControl, my SSDs are in read only, have no reserved blocks left, and is ready for the graveyard. However retired block rate is zero, there have been zero erase failures, no program failure counts, and no reallocated sectors. So sure, an attribute or two might read inaccurately thanks for a vendor being dumb but, I think that it comes down weighing out what looks right and wrong. Not all manufacturers use SMART the same way depending on the attribute. It's a pain in the ass as you very well know but, it happens. My point is that GSmartControl is a good tool to have available should you need it and at least for spinning disks, tends to work well.

I'll agree that with SSDs, it might not be the best option but, with spinning disks, I think that's a matter that is open for debate because my experience with HDDs with this tool has been very different. The library GSmartControl uses under the hood (smartmontools) is practically the thing to use if you're administering linux servers and want to check SMART information from the command line. I've found it capable for my own machine and for the servers at work so, I'm just speaking from my own experience which has been mainly with spinning disks.

I long for the day that vendors actually become consistent with this kind of thing across all kinds of drives. The problem is SMART is like SAML, people implement that parts they need and kind of munge it to work the way they want it to. It sucks half of the time as a result but, that doesn't mean it isn't a useful tool to use.

Either way, lets agree that GSmart isn't ideal for SSDs and leave it at that.


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## Violet_Shift (Oct 12, 2015)

Well, I thought my problems are over. I replaced the drive that was having errors with a WD drive, and things were fine for a few days.

Then, less than half an hour ago, while I was about to play a game (Dragon Age: Awakening for the record, I know that that doesn't matter, but I'm in a mood to post completely irrelevant things), and then as the game hit main menu, the music started looping, and after I'd killed the process I decided to restart the machine (at this point I checked RST just to be sure nothing was wrong).

I restarted the machine, and my pre-boot RAID settings tell me that the array has failed, and that one of the drives has fallen out. Not just degraded, but failed. I started the computer, and sure enough, the RAID isn't accessible, and GSmartControl tells me that the drive in slot 4 has had an "end to end" error, while RST can't even see it.

I turn it off and remove the suspect drive, and it's switched to "degraded" and the computer can see the array again, and data -seems- okay (I'm not sure if I should trust it).

It was the drive that was seeming healthy but was being thrown out of the array. And now it seems completely bricked - the computer won't even boot when it's connected.


So I know my course of action now is to replace this one, but my question is, if it once showed as failed, and the machine couldn't even see it, and now it's showing as degraded, is everything OK? Can I rebuild again and proceed as normal, while staring with suspicion at the remaining 2 ST300DM001's? (one of them is a bit newer so I might trust that a slight amount more).

Boy has this been an expensive string of computer problems.


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## FordGT90Concept (Oct 12, 2015)

I'd rebuild... you have to in order to protect the data.  I've never seen this kind of behavior so I'm scratching my head on it.


Definitely run an extended test on that Seagate drive with SeaTools.  If it doesn't generate an ID, the drive is perfectly perfect--the RAID controller is suspect.


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## Violet_Shift (Oct 12, 2015)

The computer sees it now fortunately. Every test I throw at it from SeaTools is a failure, and looking at the SMART status again shows this:


 

I think it's safe to presume that this drive has had a very bad day. (the error in the log lines up time-wise with the incident that happened today)


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## FordGT90Concept (Oct 12, 2015)

If SeaTools fails and it is still in warranty, copy down the ID and send it to Seagate.  They may send you a new drive free of charge.

Edit: http://www.seagate.com/support/warranty-and-replacements/ Should be able to skip to step 3.


It should be noted Barracuda drives aren't meant for RAID; Constellation ES are.


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## Violet_Shift (Oct 12, 2015)

Nope, it's out of warranty. 

Is it worth attempting using the "fixing" tools that the DOS version of SeaTools comes with?


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## FordGT90Concept (Oct 12, 2015)

It won't make it worse so if you want to take the time to do it, why not?  Odds of fixing it are near none though.  S.M.A.R.T. failure is a one-way trip.


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## Violet_Shift (Oct 30, 2015)

I want to thank everyone for helping me here. I had to replace two drives in the end, but I learned about the issues with the ST3000's, and I didn't end up buying more of those (like I did this time).


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## CjStaal (Nov 8, 2015)

Those disks you have are archive disks. The write head is larger than the read head, When writing it has to do a lot of writing, and basically overlaps each track, creating a smaller area for the read head to read. These drives are good for storing information long term with a lot of reads, and hardly ever any writes. In raid 5 there is a lot of writing going on. You should never use archive drives in any raid except raid 0,1, or 10, and only for long term storage/long time between writes, but you can read it whenever.


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