Disk Utility - Why are some values absurdly high?

[wade8218]

Prologue

I have a guy whom I work with, for whom I built this custom, awesome computer for him. The RAID utility for his two RAID 1 drive pairs started giving me messages pretty much as soon as this new motherboard and CPU was upgraded in his computer (refer to the PDF for this log). Note that the second RAID (2TB_MIRRORED_DATA) was created using this new motherboard. So I am concerned that part of these issues might be a result of this, I thought I would break the RAID to check the specific smart status data in a live Fedora environment and run a short SMART test, followed by benchmark data for each drive. I have screenshots of all this data, as an fyi.

Raid #1, Drives on port 1 and 3, MirroredData
Raid #2, Drives on port 2 and 4, 2TB_MIRRORED_DATA

The Attached Files

The PDF shows the log created by the RAID controller that is on the motherboard.
The zip file contains 4 images, each one named according to the port location the drive exists on.

My questions for you fellow Fedorians

First off, why is the number of "Hardware ECC Recovered" value for the MirroredData raid drives so incredibly high if the SMART status is reporting healthy? If you haven't looked at the logs yet, the only thing that's happened to these drives is a rebuild of drive 1 using the data from drive 3. That's the only plausible explanation I have for it, but what confuses me is why drive 3 would also have a really high number in this field as well? Is this cause for concern and should I get drive 1 replaced?

Secondly, on the 2TB_MIRRORED_DATA RAID, why is there such an high value for the "Read Error Rate" if the SMART status is also reporting healthy? In addition, for these drives you'll also notice that there is a pretty high "Seek Error Rate" and "Hardware ECC Recovered" values too.

And finally, why do I see values like this from time to time on various drives that SMART reports as OK but I see insane values that make me worry? I'm assuming this might be answered by now, but I'm throwing this out there now.

Thank you!!!!

I appreciate your time and help. I'd love to see some links if you have any handy referring to any information that might help me learn how to figure it out myself. I've tried looking without much success regarding that utility.

Hurrah for open source and people like you!

Edit

I meant to make the poll option read for the disk on port 02 instead of port 03. Doesn't seem I can edit the poll. I fail.

[stevea]

The general meaning of the SMART parameters is well documented, but a lot of noobs are misinformed. Not only are many raw parameterd vendor specific, but even ones that aren't are not always defined preciecly the same. Also different vendors include different attributes in their controllers.

I'd personally appreciate if you would divulge the disk make/model for each, but that's just my personal interest cropping up.

So first study the actual meaning of the raw attributes before jumping to conclusions.
Like #195 "Hardware ECC Recovered" - (Vendor specific raw value.) The raw value has different structure for different vendors and is often not meaningful as a decimal number.

http://en.wikipedia.org/wiki/S.M.A.R.T.

Note that item #1 is vendor specific too!!


Google did a report and found that no SMART parameter is a good indicator of impending failure. So I tend not to get my panties in a bunch just b/c the SMART parameters look a bit sour. Look at the "NOrmalized" and the Worst" and as long as these are well above the "Threshold" then the vendor finds the parameter OK.



So my reading is:
disk-01 - ~170 days uptime and ~175 power cycles, a large number of ECC correct and a 25 UNcorrected errors.
disk-03 - ~170 days uptime and ~175 power cycles, a large number of ECC correct and a 9 UNcorrected errors.
disk-02 & 04 - ~12 days uptime and time bignums for the vendor specific values - but no normalized or worst close to and thresholds


Well I'm sort of disturbed by drive 01 & 03, attribute #187. If you didn't have a mirror you'd have seen ~25 unrecoverable reads in ~6 months on -01. OTOH so long as these are in mirror they are pretty safe. You are quite unlikely to get coincident block errors on both copies of the mirror.

This is another opinion on attribute 187,
http://kb.acronis.com/content/9122

Personally I'd run both the short and long self-tests on both drives, and perform write-reads of the entire surface. If the vendor has a test tool (like seatools, or the WD equivalent) I'd run that too. That takes a long time for a 2TB drive. If the SMART error logs look bad - then replace.


The 'smartctl' command is your friend for the tests and logs, but I don't know enough to guide when they are behind a RAID controller.

[Dan]

Poll fixed

[wade8218]

Originally Posted by Dan

Poll fixed

Thank you.

---------- Post added at 04:32 PM ---------- Previous post was at 04:31 PM ----------

@stevea

Thank you for your response. I will get the information regarding the specific information to you hopefully in a few hours here. I will also see about reading up on your links while running the long tests ( I will have to break the RAID to do that). :P I can always rebuild them later without forcing this guy to be down from his computer.

Quite handy if you ask me, this guy doesn't want his computer down for any real length of time. Professor and gamer. :P

[wade8218]

Originally Posted by stevea

The general meaning of the SMART parameters is well documented, but a lot of noobs are misinformed. Not only are many raw parameterd vendor specific, but even ones that aren't are not always defined preciecly the same. Also different vendors include different attributes in their controllers.

I'd personally appreciate if you would divulge the disk make/model for each, but that's just my personal interest cropping up.

Well, the guy I needed to do this for has been super busy and hasn't really allowed me near his computer for much or hasn't been home. :P He doesn't want his computer down long enough to even put the drives in now for me to get the second set to test cause of work priority stuff.

Anyway, I tested one from each part of the RAID pairs doing an extended test and a read/write benchmark test (which means I had to delete all the data to do that test). Tomorrow I will put the drives back in (when the guy isn't home) and leave the utility open so he can rebuild the RAID when he goes to bed, and then I'll snag the other two to test them here soon hopefully. :P Screenshot information attached.

And here is the HDD info as well.
-------------------------------------------------
Disk 01
-------------------------------------------------
Manufacturer: Samsung
P/N: A6291-B741-A3UBS
S/N: S1VSJD2ZC04805
Firmware: 1AG01181
Model: HD103SI
HDD P/N: HD103SI
LBA 1,953,525,168, 1000 GB/R54/32M


-------------------------------------------------
Disk 03
-------------------------------------------------
Manufacturer: Seagate
P/N: 9TN158-513
S/N: 5XW2TGZE
ST32000542AS
Firmware: CC38
Date Code: 11484
Site Code: WU
DOM: 05/2011
2000 GB

I'll read through the information you posted here later now that I will be getting a chance to work on the drives. Thank you for your response! I really appreciate it!!!