Replaced Failed Drive, Rebuilt Array, Rebuilt Drive Lost All Data


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14 minutes ago, gary.e.mckee said:

The last parity check was last done 15 Oct. and completed with no errors. 

Was that after all these replace / rebuilds?

 

I always recommend a non-correcting parity check after any rebuild just to confirm that the rebuild went as expected.

 

17 minutes ago, gary.e.mckee said:

It takes a little over 3 days to complete.

Do you have port multiplier or something? My 8TB parity check always completes in less than a day.

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The last parity check was completed after the system settled down. 

 

My system has 80 TB of hard drives not counting the 16 TB of parity drives.  It always takes that long as far back as I remember, including the normally scheduled parity checks.  My processor is an old 3 core AMD processor.  Not sure of the speed.

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Total capacity isn't important for parity check speed. Size of the largest parity disk is the main deciding factor since the disks are read simultaneously unless you have controller bottlenecks. With dual parity an old CPU might be the bottleneck since parity2 is a more complicated algorithm.

 

If you are confident your system is stable now, you can try to copy the data from that original disk3 to the new disk3. Copying the data would be simpler if you had the Unassigned Devices plugin, but if you don't, you probably can't install it without upgrading Unraid first.

 

Or, you can New Config / Rebuild Parity with that original disk3 back in slot3.

 

In any case, you should definitely upgrade. Upgrading has many advantages as mentioned, but upgrading from such an old version has a few details that may need to be worked through.

 

 

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OK, so I don't screw things up more, how do I do the New Config/Rebuild Parity?  \

 

I assume I shut the array down and remove disk 3.  From there do I bring the array back up?  What would be the specific steps.

 

If you don't mind, could you tell me how to do it step by step so I don't muck thing up worse than they are?

 

 

Also thanks for all your help!  It is really appreciated.

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First, I am going to bed after this post, so if you want to wait I will check back tomorrow.

 

I don't have your version in front of me obviously so some specific details may be slightly different, but basically New Config has worked the same since I have been using Unraid (4.7). It is just a way to reset your disk assignments, let you assign any disks however you want, and optionally (by default) rebuild parity. Any disk assigned to a data slot will not be changed.

 

Make careful note of your disk assignments so you can be sure to get them all assigned correctly. It is especially important that you not assign any data disk to any parity slot, since it would be overwritten with parity.

 

Go to Settings - Disk Settings and disable autostart. It shouldn't really matter but just in case.

 

Then shut down, remove new disk3 and replace with original disk3. Reboot, then

 

Go to Tools - New Config

 

Not sure of the wording in your old version. It will probably let you keep your assignments as they are, or keep only some of them. It doesn't matter at that point, it is just for convenience that it lets you keep them, because


Before starting the array, it will let you change any assignments you want to change. Keep all assignments as they were except assign the original disk3 to data slot3.

 

Then, when you start the array, be sure that you don't check the box saying parity is valid, because it isn't due to a different disk3. Then starting the array will begin parity rebuild. If for some reason it shows any data disk is unmountable or no filesystem, DON'T FORMAT! Shouldn't happen except we don't know for sure about that original disk3. We can deal with repair later if necessary.

 

Ask if you have questions. Post diagnostics and maybe screenshots if something doesn't seem right.

 

 

 

 

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I got got to the step of selecting New Config.  I have a choice of retain the current configuration - Apply or Done.  Nest to the statement Retain Current Configuration I have a box that says None Or All, Parity Disks, Data Slots, Cache Slots.   I would assume I select data slots then done, but I don't want to screw thing up any more than I have already.  Is selecting data slots correct then apply or done?

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27 minutes ago, gary.e.mckee said:

I got got to the step of selecting New Config.  I have a choice of retain the current configuration - Apply or Done.  Nest to the statement Retain Current Configuration I have a box that says None Or All, Parity Disks, Data Slots, Cache Slots.   I would assume I select data slots then done, but I don't want to screw thing up any more than I have already.  Is selecting data slots correct then apply or done?

It is really up to you as to which you will find most convenient.   I normally use the option to retain all settings and then when I return to the Main tab make any appropriate adjustments before starting the array (as that typically involves the minimum amount of effort for the sort of change I am considering).   The end result should be the same.

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OK, it took 3 days and 7 hours.  When finished it said rebuild complete with 0 errors.  Disk 3 now is empty.  (I lost 8 TB of data that was on that hard drive).  I am back to where I was when I started this recovery. 

 

My plan now, unless somebody had better suggestions, is I plan of doing the following:

 

Down load latest stable of UNRaid.

 

I will remove all my hard drives.

 

I have 2 unused 8 TB hard drives I will use.

 

I will format both parity disks and the empty disk 3.

 

I will use one hard drive for parity and the other drives as data.  I will copy data from the remaining drives to the newly set-up UNRaid set-up.

 

After I remove the data from the drives that have data on them, I will format those drives and install them as more data drives.  When I am finished, I should have at least one unused 8 TB drive left, which I will install as a second parity drive.

 

I will then try to recover any missing data from my online backup or from other locations I have on the internet.

 

Am I missing anything?  I know this will take a long time, but I think all my options have just put me back in the same place.

 

Any other suggestions? 

 

Thanks

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Let me start by bring some relevant quotes from the previous page

 

On 10/19/2020 at 3:18 PM, trurl said:

So, was the original disk3 the same disk that was in that slot last year? If so, do you still have that disk and haven't changed it in any way since you removed it for replacement?

On 10/19/2020 at 3:53 PM, gary.e.mckee said:

the old disk 3.  I found it.  If necessary I could do what I have proposed below, but if I can recover the data from the old disk 3 that would be great.

 

No, I formatted it in another machine to see if it would be usable again.  Dumb mistake made before I started this post.

On 10/19/2020 at 4:03 PM, gary.e.mckee said:

I misread my info.  The disk I thought was disk 3 was not the old disk 3.  I'm not sure if I have the old disk 3.  I will look at my old disk and see if I can see any that look like they could be it.

On 10/19/2020 at 4:08 PM, gary.e.mckee said:

I did find the old disk 3 and it does have the file structure and videos on it.

On 10/19/2020 at 8:10 PM, trurl said:

What are the last 4 characters of the serial number of that disk?

On 10/19/2020 at 8:28 PM, gary.e.mckee said:

The last 4 are 1pry.

I will comment further on my next post.

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16 hours ago, gary.e.mckee said:

When finished it said rebuild complete with 0 errors.  Disk 3 now is empty. 

You did New Config with the original disk3, correct? If so it was rebuilding parity, and it would not have changed anything on that original disk3. So you must have formatted the original disk3 at some point.

 

But, there was some confusion earlier about which disk was the original disk3. At first you said you had formatted it, but then you said you found the disk and it had the files on it. Is the disk with serial ending 1pry the disk you assigned as disk3 when you did New Config?

 

I will save further comment and wait for answers.

 

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The original disk 3 from a year ago was ending in pry.  That disk had data on it.  I installed it in the disk 3 slot and did the new configure.  The system did a parity check that took 3 days & 7 hours.  That disk now had no data on it.  The confusion on what disk I formatted was caused when the hard drive I had in the disk 3 slot failed and the system said to replace it.  I put a new drive in and the system said I had to format it, then the rebuild happened but when the rebuild took place there was no data on it.  Since that disk was empty, and I didn't feel that the format was required, I put a different hard disk in disk 3 slot.  The rebuild took place and again no data was installed on it.  I then (per your suggestions) installed the old hard drive serial number ending in pry that had data in it.  I did the New Configure and UNRaid performed a parity check.  This took 3 days & 7 hours.  When it completed, that drive had no data on it any more.  I suspect somewhere along the line UNRaid thinks disk 3 should be empty and attempts to make any disk installed an empty disk.  As far as I know now I do not have any  disk that had been installed as disk 3 that may have any data on it.  I think the hard drive with serial number endiny in pry was an original drive in my UNRaid set up.

 

 

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30 minutes ago, gary.e.mckee said:

did the new configure.  The system did a parity check that took 3 days & 7 hours.  That disk now had no data on it.

New Config does parity rebuild, not parity check. As mentioned,

3 hours ago, trurl said:

it was rebuilding parity, and it would not have changed anything on that original disk3.

 

30 minutes ago, gary.e.mckee said:

I suspect somewhere along the line UNRaid thinks disk 3 should be empty and attempts to make any disk installed an empty disk. 

No, it doesn't work like that. In fact, New Config makes it forget all about all disks and just takes them as they are and goes from there.

 

Assuming you didn't format it while you were rebuilding parity, then it must not have had any data on it when you did New Config.

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I checked this disk ending in pry before I installed it in the UNRaid box.  It had data on it.  When I did the New Config, it said something to the effect that it would do what you said and , for lack of a better description, take each disk and put it in the UNRaid based on what was on the disk.  After that was done, UNRaid did a parity check at which time all the data on disk 3 was gone.  The New Config part did not seem to take very long as opposed to the parity check.  I did not format disk 3.

 

I just finished going through all my SATA hard drives regardless of the size and none of them had files on them except for one that had Music on it and it compared to what I still have on UNRaid for the Music disk that it replaced.

 

I still can not access any of the video files that are one any of the shares that disk3 is part of.  I'm beginning to think I should just start from scratch as laied out above instead of wasting more time.  In starting from scratch I can do an upgrade to the latest level of UNRaid and possibly reorganize my layout.

shemp-diagnostics-20201026-1320.zip

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9 minutes ago, gary.e.mckee said:

The New Config part did not seem to take very long as opposed to the parity check.

As mentioned, it was a parity rebuild, not a parity check. Not sure what you mean about the New Config not taking very long. It doesn't take any time at all except what time you take in assigning disks. Starting the array is where the New Config takes effect, and at that point it has already begun rebuilding parity.

 

If there was some additional time then that makes me suspect you formatted disk3 again. Format does take a few minutes.

 

Upgrading might help at least get things off to a better new start.

 

Just thought I would comment on something you said earlier.

On 10/25/2020 at 5:41 PM, gary.e.mckee said:

I will format both parity disks and the empty disk 3.

There is no need to format anything when you start over. Parity doesn't even have a format since it has no filesystem. When you setup your disks again, parity will rebuild, completely overwriting anything that is already on parity. Doesn't matter if the disk has old parity information, doesn't matter if you have formatted it to some filesystem, doesn't matter if it is full of files. If a disk is assigned as parity it is completely overwritten with parity.

 

And empty disk 3 is already formatted. You don't want to format anything else or you will lose that data too.

 

You seem to still have some incorrect idea of what "format" does.

On 10/19/2020 at 1:32 PM, trurl said:

"Format" means "write an empty filesystem to this disk. That is what "format" has always meant in every operating system you have ever used.

  

 

 

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I know what format does.  That is why I was surprised when UNRaid said that one time and that time only that I needed to format the disk.  That is the only time I did a format on any hard drives on my UNRaid system.  I said the New Config did not take very long because I don't recall it taking any time.  I was not sure if it would be instantaneous or take hours.  That was just some information that I though might be helpful if the New Config  should take a measurable amount of time.  Thanks for clearing that up for me.

 

Its good to know I don't need to format old parity drives in a new system.  The only disk I would format are disks that  have data on them that I had already copied to the new system.  The idea for formatting the drives that I copied data from is so I know there is nothing on them that could potentially confuse how I would be setting things up.  If I format the drive, then I know there is nothing on it and it would be like using a new drive.

 

I have an unused computer similar to the one I am using for my UNRaid machine, except that the number of processor cores are different.  That machine was working fine, till I shut it down because I am now using a different computer for what it was used for.  That should help alleviate any concerns about hardware issues.  The only common things from the old (present ) machine and the new machine would be the hard drives.

 

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10 hours ago, gary.e.mckee said:

The idea for formatting the drives that I copied data from is so I know there is nothing on them that could potentially confuse how I would be setting things up.

On the other hand, if you don't format them, then you have an extra copy. Keep things straight by the disk serial number, that is how Unraid does it.

 

10 hours ago, gary.e.mckee said:

If I format the drive, then I know there is nothing on it and it would be like using a new drive.

However you might reuse an old disk, it isn't necessary to format it before using it in Unraid.

 

If you use a disk, whether old or new, to rebuild another disk, the rebuild will completely overwrite every bit of the disk, so it doesn't matter what was already on the disk.

 

If you add a disk, whether old or new, to a new slot in an array that already has valid parity, then Unraid will clear that disk so parity remains valid. A clear disk (different than an empty disk) is all zeros and so has no effect on existing parity. After clearing, then Unraid will make you format the disk (at which point it becomes an empty disk) so it can be used.

 

And finally, if you do format a disk (thus making it an empty disk) before adding it to a new slot in an array that already has valid parity, Unraid will clear that disk so parity remains valid, then make you format it so it can be used.

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