Best way to replace disks

[Starteck2002]

I'm running an HP Microserver Gen 7:

 

Parity - 8TB

Disk 1 - 8TB (Used 7TB)

Disk 2 - 8TB (Used 7TB)

Disk 3 - 2TB (Used 330GB)

Disk 4 - 500GB (Used 532MB)

Disk 5 - 500GB (Used 532MB)

Disk 6 - 500GB (Used 532MB)

Disk 7 - FREE (no disk in caddy)

Disk 8 - FREE (no disk in caddy)

Disk 9 - FREE (no disk in caddy)

Cache - 480GB SSD

 

I want to replace disks 4,5,6 and populate the three empty caddies with 6 x 2TB drives.  What would be the best way of doing this?  Is there an option to 'remove' drives from the array or do I just shut down, pull all drives, replace with new, power up and let Unraid do it's stuff?

[FreeMan]

Since you have a single parity drive, pulling 3 perfectly good disks will leave your server without any way of rebuilding their contents. If you had dual parity drives, you could rebuild 2 drives from the parity protection. unRAID cannot handle 3 missing drives no matter what your parity configuration is.

 

Preclearing your new disks isn't required, but it's suggested in order to help eliminate infant mortality in new drives. Check out the "Preclear Disk" plugin for more details.

 

Once you've done that (if you're going to), I'd suggest that you put new 2TB drives into slots 7, 8 & 9. Use a tool like MidnightCommander, the Krusader or Dolphin docker, or the unBalance plugin to migrate all the data off of disks 4, 5 & 6 to any of the other drives you feel like moving it to. You could put it all on one of the new 2TB drives, you could distribute it across the 3 new ones you've added, whatever floats your boat.

 

Once you've confirmed that your data has been successfully moved, power down (or stop the array if they're hot-swap caddies), pull the 500GB drives, replace them with the new 2TB drives, fix up the disk assignments in the unRAID config, start everything back up and enjoy your extra 10.5TB of disk space.

[MikeyJeff]

Hi folks, I have a similar question regarding replacement of an incumbent disk.

I have detected SMART errors (only a few, but it is an old disk) on my "disk5" which is a 2TB WDC Green disk from years ago.
Rather than take a chance that the disk is failing, I think it makes sense to replace this disk with a nice 6TB WDC Red brand new drive.

 

What is the best procedure to accomplishing this?

 

From what I can gather, given I have taken all the data off this 'disk5' as a precaution, do I simply unassign this disk, allow unRAID to trust the new configuration (would it still need to build parity given the drive is empty?) - then remove the disk, add the new one, and allow it to be pre-cleared, formatted to XFS and then it be active in the array?

 

The reason I don't want to simply replace the old drive with a new one is the old drive is 'reiserfs' and I don't want it to rebuild an empty drive with a legacy file system - unless that's not what happens given the disks are of different sizes.

 

If there is another way to effect this outcome - i.e. take the empty drive out of service, put the new drive in, have it preclear and format XFS and enter service, let me know!

 

Best wishes and thanks in advance!
Cheers,

Mike

[JonathanM]

29 minutes ago, MikeyJeff said:

What is the best procedure to accomplishing this?

Since you don't need the data on the drive your are replacing, you have 2 options. Rebuild the drive, or rebuild parity. Pretty much identical in terms of time and resource usage.

 

Drive format can be done before you replace if you want, stop the array and change the desired format on the drive in question.

 

Just because you emptied the drive, it's not clear, it still has a format and deleted files on it, so parity would still be wrong if the drive was simply removed.

[MikeyJeff]

Thanks for that - makes sense. 
So essentially my procedure would be to:

1) Stop my array

2) Unassign "disk5" as "no device" (I can't remember what happens after I click this!)

3) Go into "New Config"

4) Preserve current assignments (All)

5) Start array which will rebuild parity??

 

I just want to make sure I'm doing the right thing in the right order as the rest of the array is working perfectly and I'd hate to make a mistake! Once the new config is operating well with parity rebuilt, I will purchase a brand new disk, insert it into the array, have it pre-clear, format as XFS, and be up and running but feel I should remove this disk that is becoming problematic before replacing with a new disk.

 

Let me know if my procedure is right here!

Thanks again,

Mike.

[JonathanM]

29 minutes ago, MikeyJeff said:

Thanks for that - makes sense. 
So essentially my procedure would be to:

1) Stop my array

2) Unassign "disk5" as "no device" (I can't remember what happens after I click this!)

3) Go into "New Config"

4) Preserve current assignments (All)

5) Start array which will rebuild parity??

 

I just want to make sure I'm doing the right thing in the right order as the rest of the array is working perfectly and I'd hate to make a mistake! Once the new config is operating well with parity rebuilt, I will purchase a brand new disk, insert it into the array, have it pre-clear, format as XFS, and be up and running but feel I should remove this disk that is becoming problematic before replacing with a new disk.

 

Let me know if my procedure is right here!

Thanks again,

Mike.

Close, but not quite. Move step 2 below 4 and you should be good.

1

3

4

2

5

[MikeyJeff]

Thanks so much for that!

 

Just so I'm clear - do I physically disconnect the disk prior to undertaking the above procedure - I can't seem to see when I'd physically disconnect/remove the drive in the above.

 

Cheers!
Mike

[JonathanM]

4 minutes ago, MikeyJeff said:

do I physically disconnect the disk prior to undertaking the above procedure -

Doesn't matter, the procedure will work with or without the drive attached.

[MikeyJeff]

Okay makes sense, re: drive attachment.

 

The only thing I'm not sure about is why I would need to go and "New Config" and "Preserve Current Assignments" first when I haven't made any changes to the array (yet), apart from stopping it. Wouldn't I only need to unassign the disk or does forcing New Config prior to making any drive modifications perform an important preparatory task pre-unassigning the disk?

Thanks so much for your quick responses - much appreciated!

[JonathanM]

12 minutes ago, MikeyJeff said:

why I would need to go and "New Config" and "Preserve Current Assignments" first when I haven't made any changes to the array (yet),

Because you can't make changes to the array before you do the new config.

[MikeyJeff]

Hi guys - I have tried to undertake the method above, and have followed those instructions to the letter, but it doesn't seem to be taking the disk out of service, it keeps wanting the missing disk. Just for clarity, I used these steps:

 

1) Stopped the Array

2) Selected "New Config" 

3) Preserved Current Assignments (All)
4) Clicked "Yes I want to do this" and pressed "Done"

5) Took Disk5 out of service by unselecting it in my assignment and it then becomes "missing disk"

6) Brought the array back on line.

 

It simply says "Missing disk - please replace disk" - I'm clearly not doing something correctly here.

 

I have a brand new 6TB disk that I want to pre-clear and replace Disk 5 with (but Disk 5 has nothing on it so don't want to rebuild it, and wish it to be in the XFS file system, not RFS), but it seems to want the old disk.

 

Perhaps there is a better way to get the desired outcome - Disk5 2TB RFS to be replaced with a 6TB XFS disk.

Welcome the brains trust on this!

 

best wishes and thanks,

Mike.

[MikeyJeff]

Just on this, I have the Array in this current status:

 

 

Am I now in a position to remove "sdg" (Disk5) from the array physically - replace it with the new 6TB WD Red hard disk that I have just purchased and it will then pre-clear, etc. format the disk as XFS, and I can then assign it to the array as new disk5 rather than try to rebuild old disk5 from the parity image?

 

Thanks again!
Mike.

[JorgeB]

New config didn't take, all disks must change to a blue icon, repeat it.

 

50 minutes ago, MikeyJeff said:

Clicked "Yes I want to do this" and pressed "Done"

You missed the "Apply"