Downgrading Array Disks

[bombz]

Hello,

I have been working on my server, and these days as disks are getting larger, I am wondering what the process is to combine (2x) disk(s) to (1x) disk(s). 

For example:

I have a total of 12 disk(s) in my array. I want to combine (2x) of these disk(s) but not have UnRAID detect a missing disk in my array. What is the best method to shrink my physical disk(s) array. 

I was reading this, and wanted to make sure I am on the correct track for doing this procedure when the time comes :-) 
https://wiki.lime-technology.com/Shrink_array

Thank you!

Edited September 26, 2017 by bombz

[tdallen]

You've linked the correct procedures in the Wiki.  Copy data off the drive to be removed (mc, unBalance, Krusader, etc).  If you feel comfortable rebuilding parity, it's a straightforward New Config omitting the drive to be removed.  If you want to preserve parity there's the slightly more complex clear and remove method.  I did this recently and since I felt good about both the remaining disks in the array and a recent full backup, I just went with the New Config.

[bombz]

OK
So basically I want to copy all data over to another drive or device first.
Remove any global shares
MAKE NOTE of the drive assignments ( via screenshot etc ) 

Tools > New Config (etc)
Once parity is rebuilt with the new config and data is secure, I can then add the new drive

It always scares me doing these parity syncs and moving devices around, i don't want to lose data obviously 

[Vr2Io]

In fact, I don't understand what you are doing.

 

combine (2x) disk(s) to (1x) disk(s), I suppose you have some larger disk i.e. 4TB disk to replace two 2TB disk

 

> Remove any global shares
> MAKE NOTE of the drive assignments ( via screenshot etc ) 

> Tools > New Config (etc)

If copy data to 4TB, then why remove shares (delete data) on those old disk. The old disk could be a backup / last chance of your data.

And What is the purpose of make screenshot then new config ?

 

> Once parity is rebuilt with the new config and data is secure, I can then add the new drive

You want add 6 disk in 5 times ? Add disk to a protected array, unRIAD will just clear the new disk. You want clear it and copy data in ?

 

Copy operation have draw back, the directory date/time can't retain, would you concern directory order change ?

 

Usually, shrink disk no. in an array, I think 2 general method would be use

1) Copy all data to new disk then remove all old disk and plugin all new disk and rebuild parity. ( You have 2 data copy anytime )

2) Ensure array were protected by parity (single or dual) and no error, then replace half no. of disk by new disk (rebuild each time). Then copy another half old disk's data in new disk's remain space. Finally, take out those old disk and rebuild parity. ( You also have 2 data copy anytime )

 

Method (1) straight forward and safe, method (2) should be faster then (1) but rather easy make mistake.

 

 

Edited September 26, 2017 by Benson

[bombz]

OK.
I thank you for the response. Again I am new to this process. I am running out of room/space in my case, so I want to remove some smaller size disks, and replace them with a bigger disk. 

So it seems I need to add the new disk to the array, copy data from the (2x) disks I am removing to the newly installed one. Then remove the (2x) disks (via gui) and run a new parity sync. 

 

I want to free up space in my case, so I can get dual parity up and running successfully. 

 

I will read over your instructions in detail some more later as I am just heading out. I appreciate the community support SO much. I love UnRaid ! 

 

I am deferentially confused with the process. I have read the Wiki over and over, it makes sense, I suppose I am nervous of data loss

01) removing (2x) 1.5 TB disks
02) replacing with (1x) 4TB disk

My plan.

Take screen shots of WEBGUI (desk setup) for visual reference (in case needing to re-assign disks)

01) Add 4TB disk to array (new disk)
02) copy all data from (2x) 1.5TB disk to the new 4TB disk added in the array
03) remove (2x) 1.5 TB disks from array
04) parity sync and protect array 

I think I am doing this correct ?  

 

I don't have to remove (2x) disks at once, I can do it the slow and steady way, and just do one at a time, which is probably much wiser 

Edited September 26, 2017 by bombz

[tdallen]

Your procedure sounds correct.  I'd pull both the 1.5 TB disks at once.  You may want to turn on Turbo Write (in my sig) during the copies to speed things up.  Also, be careful that you copy from one disk share to another disk share - don't use user shares during this operation.  Finally, I would use copy rather than move - its ok to have data on the drives you are pulling.  What tool are you going to use to copy the data around?

[bombz]

Ah, new forum, I just noticed sigs are off by default. I have adjusted and added mine back too 

 

I always browse my array by my disk mapped drives. I never WRITE to shares. Shares are there just for READ ONLY. 

 

As for moving/copying  data (which is slow in general)
I have found copying to array from local PC or Disk-to-Disk within array tends to be slower then what i have seen in the past

perhaps it is due to not having turbo mode enabled at all?

 

I am using Taracopy for disk copy. move (Windows PC) 

Edited September 27, 2017 by bombz

[tdallen]

Disk to disk on the server with turbo write should be fastest, it eliminates the network.  I tend to use Midnight Commander (mc command) in a screen session but others prefer the Krusader docker or rsync.

 

Writing new files from your PC to a user share is fine, but this type of maintenance operation needs to be done from one disk share to another disk share.

[bombz]

So I use my disk mapping from windows PC

I just browse from one disk and move to another. I suppose I am not doing this efficiently. I am all ears to learn the specifics on how to do this better for sure! (stupid windows) lol :-)  

[tdallen]

Both mc (character based) and the Krusader docker would be more efficient by removing the network.  Both are twin panel file managers - source on one side, target on the other.  To try mc just login to your server and type mc.  You'd get Krusader from Community Applications.  You can also try the unBALANCE plugin, also from Community Applications - it's designed to help in siutations like this.  If you decide you like mc, you should also look into screen.

[bombz]

OK thanks for the help there.
I am new to how some of these applications well. I know I am not utilizing some of my server functions efficiently.

Right now I am in a rebuild/sync (due to another concern with disks) so I have to focus on getting my array 100% operational, then move to the next task of shrinking the array by removing smaller physical disks for larger ones, and adding dual parity.

Every task takes some time :-) 

I am going to keep this thread open for the time being, as I am sure I will have some more questions. Still trying to figure out why those other plugins post "ERROR"