Preclear to clear "current pending sectors"


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Ok last question for now, I see Unassigned Devices is a plug which allows you to copy data from drives not in the array.  Can I also assume that even though disk 3 is unmountable I can still add it outside the array and copy files from it? 

 

At what point should I preclear my new 4TB drive?  Now or should I first do a new config with the disks you suggested and let parity build, then preclear my new disk and add to the array?

 

I'll probably need some help though with the Unassigned Devices...so don't disappear on me ;-)

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Ok last question for now, I see Unassigned Devices is a plug which allows you to copy data from drives not in the array.  Can I also assume that even though disk 3 is unmountable I can still add it outside the array and copy files from it? 

 

At what point should I preclear my new 4TB drive?  Now or should I first do a new config with the disks you suggested and let parity build, then preclear my new disk and add to the array?

 

I'll probably need some help though with the Unassigned Devices...so don't disappear on me ;-)

Does it actually say disk3 is unmountable? I was just assuming it was disabled based on your diagnostics. If unmountable that suggest filesystem corruption on the emulated disk and possibly the actual disk. And you won't be able to get any files from it until the filesystem is repaired. Post a screenshot.

 

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I would like to make another comment about all this, and I will probably remind you again later.

 

You should setup Notifications, and then don't ignore them when it is telling you that you have drive issues. If you look on the Dashboard right now it is probably showing you that multiple disks are having issues.

 

unRAID works very well when you have a single disk with problems (2 with dual parity). It is designed to handle that situation very easily. But when you let more than that many disks become unreliable you wind up in a big mess that will take a lot of effort to fix and you may not be able to recover from.

 

 

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Sorry, you are

Ok last question for now, I see Unassigned Devices is a plug which allows you to copy data from drives not in the array.  Can I also assume that even though disk 3 is unmountable I can still add it outside the array and copy files from it? 

 

At what point should I preclear my new 4TB drive?  Now or should I first do a new config with the disks you suggested and let parity build, then preclear my new disk and add to the array?

 

I'll probably need some help though with the Unassigned Devices...so don't disappear on me ;-)

Does it actually say disk3 is unmountable? I was just assuming it was disabled based on your diagnostics. If unmountable that suggest filesystem corruption on the emulated disk and possibly the actual disk. And you won't be able to get any files from it until the filesystem is repaired. Post a screenshot.

 

 

Sorry you are right.  It says "disabled - contents emulated".  I used the wrong terminology.

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So back to part of my question...

 

At what point should I preclear my new 4TB drive?  Now or should I first do a new config with the disks you suggested and let parity build, then preclear my new disk and add to the array?

 

Oh and I guess I should ask now.  To create a new config, do I just unassign the drives, then start the array and it will see it as a new config?  I've never had to create a new config from an existing one.

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Go to Tools - New Config and it will let you assign the drives any way you want. Make very sure you don't assign a data disk to the parity slot or it will be overwritten. Then Start will build parity from the assigned disks. Once you have parity building you should be able to preclear the new drive at the same time, or you could just wait till parity is done to make things less complicated. Preclearing is going to take a lot longer than the parity build anyway.

 

Possibly after you get the data off of the problem disks you may be able to reuse disk 7 and 10 if you can get the pending reallocated by preclearing. I wouldn't even try to reuse disk4, it just has way too many problems.

 

You should take a screenshot to help you keep track of which drives are which so when you have set a new configuration you will know. Just pay attention to the last 4 characters of the serial number of each disk. This information is also in the diagnostcs you posted earlier but a screenshot might be easier for you to work with. Print it out and make notes on it if you want.

 

It is going to be several days before we are done with this, and no doubt there will be more questions along the way. And no guarantees.

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Here you are

I will also put it here

Parity HGST_HDN724040ALE640_PK2338P4HD56KC - 4 TB (sdh)

Disk 1 WDC_WD10EARS-00Y5B1_WD-WMAV50750561 - 1 TB (sdi)

Disk 2 WDC_WD10EARS-00Y5B1_WD-WMAV50750600 - 1 TB (sdj)

Disk 3 WDC_WD20EARX-00PASB0_WD-WCAZAH610920 - 2 TB (sdb)

Disk 4 Hitachi_HDS5C3020ALA632_ML0220F31BG4ED - 2 TB (sdf)

Disk 5 ST31500341AS_9VS14YP2 - 1.50 TB (sdg)

Disk 6 WDC_WD20EZRX-00DC0B0_WD-WMC301160316 - 2 TB (sdm)

tower-diagnostics-20170108-0948.zip

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OK. I think this diagnostic contains everything we'll need going forward. In addition to the drives you listed as assigned and are building parity on, the other disks are still attached, except

 

cache device: sde ST3320620AS_3QF0M37V (sde)

 

isn't attached. It looks like you have another unassigned drive instead

 

HGST_HDN724040ALE640_PK2334PEK7EH9T (sde)

 

Is this the drive you're preclearing?

 

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I just spotted something odd.  I can see see my shares.  Before I did a new config I had a share for Movies, TV Shows etc.  THey are still there.  What's odd is under TV Shows I'm seeing shows that aren't on any of the disks in the current config....

 

How do I remove shares such as Movies, TV Shows etc.  I don't see a delete on the shares tab. 

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I just spotted something odd.  I can see see my shares.  Before I did a new config I had a share for Movies, TV Shows etc.  THey are still there.  What's odd is under TV Shows I'm seeing shows that aren't on any of the disks in the current config....

 

How do I remove shares such as Movies, TV Shows etc.  I don't see a delete on the shares tab.

User shares are just the aggregate of all top level folders on cache or array disks. Even if you don't actually create the shares you still get them if they are top level folders. And you can't remove shares if those top level folders still have files in them.

 

Don't know exactly what you are seeing, but any files you see are on the assigned disks.

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Yes, I'm preclearing that drive.  It's plugged in like all my other drives via SATA

Not sure why Diagnostics didn't get SMART for it then. The only HGST in the smart folder of your diagnostics is the parity drive.

 

Well, preclear report when its finished will be good enough.

Sorry, I was looking at the wrong diagnostics. That HGST is there, but SMART is disabled on it. If the preclear doesn't give it to us, you need to turn it on like so:
smartctl -s on /dev/sde

and post another diagnostic.

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I'll just put this here for future reference as we work through this, so we don't have to continue to dig through the diagnostics.

 

To summarize, SMART for all assigned drives looks OK. There is this on disk5

Serial Number:    9VS14YP2
  5 Reallocated_Sector_Ct   0x0033   100   100   036    Pre-fail  Always       -       5

but nothing to worry about for now.

 

Now for the unassigned disks. You will be copying data from all of these to your array or somewhere, and possibly you can re-use some of them.

 

Serial Number:    WD-WCAZAH723964
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail  Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       0
198 Offline_Uncorrectable   0x0030   200   200   000    Old_age   Offline      -       0

This is the former disk3 that was disabled. Its SMART looks OK though, and maybe it could have been included in the new configuration as bjp999 suggested but no point now since you already have parity built. And since we don't really know why it was disabled maybe just as well. You might do an extended SMART test on it and if it passes you can use it again.

 

Serial Number:    WD-WMAZA0585469
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail  Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       175
198 Offline_Uncorrectable   0x0030   200   200   000    Old_age   Offline      -       1

This is the former disk4. That is way too many pending for my comfort. I wouldn't trust this in my array.

 

Serial Number:    WD-WCAZAE783457
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail  Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       3
198 Offline_Uncorrectable   0x0030   200   200   000    Old_age   Offline      -       54

This is the former disk7 which was throwing a lot of read errors. Offline_Uncorrectable is a bit high. Not sure what everyone thinks about this, but I don't think I would trust it in my array.

 

Serial Number:    WD-WCAZA0182929
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail  Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       3
198 Offline_Uncorrectable   0x0030   200   200   000    Old_age   Offline      -       2

This is the former disk10. Not perfect, but maybe it can be used again. Try preclearing it a few times to see if you can get the pending reallocated, then do an extended SMART test. *edit* This disk was XFS.

 

Still waiting for SMART on the new disk,

HGST_HDN724040ALE640_PK2334PEK7EH9T (sde)

 

*edit* All disks were ReiserFS except as noted. Cache drive ST3320620AS_3QF0M37V was btrfs but not currently attached.

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The last one is still preclearing, at 40% Post Read.  Didn't the new config do a parity?.  Why would I do one again?

 

Since my new case will only have 5 bays and I have one 4 TB Parity drive, a new 4TB drive, that only leaves me with 3 more drives.  In my current config I have two 2TB drives that I will probably use, so that just leaves one from those you listed above that I would use, either disk 10 or 3.  So overall I should be ok.  The biggest test will be to see what I can copy off those drives. I ran a spotcheck on a number of movies across the drives in my new config and so far I haven't found any problems.

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Ok, preclear completed successfully.  I don't see where I can find a detailed report though.  In the video tutorials, it indicates a blue dot next to the drive, but I don't have one.  I'm guessing the video is out of date.

Been a while since I needed a preclear. Post a screenshot.

Actually, if it said it was successful the only thing we need is the SMART attributes from the drive. If you click on the drive in Unassigned Devices it should take you to that drive's page where you can get the attributes if they are available. Otherwise you may need to enable SMART as I said earlier.

That HGST is there, but SMART is disabled on it. If the preclear doesn't give it to us, you need to turn it on like so:

smartctl -s on /dev/sde

and post another diagnostic.

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