Shrink array from two drives + parity to 1 drive + parity

[Destynx]

Just build our new unraid server, we have 3*2tb for the array, for a total of 4tb + parity disk.

A few days ago finished preclearing all the drives, created the array and did a parity sync. Everything seemed okay.

I started moving data onto the array, when suddenly one of the 2tb drives failed, which resulted in the contents being emulated.

Still have all the original data on seperate drives, but I'm trying to shrink the array to a 2tb + 2tb parity so I can continue moving data onto the array and not losing the old data that's already on there, so I can later expand it again when we get a replacement drive. Problem I'm having is that shrinking the array by this method didn't work:

Stop the array.

Run new confing under tools

Select all, press apply and done

Drives are now unassigned.

 

Select the good 2tb drive as Disk 1 and the old parity disk as the parity disk.

Started the array, and it says Parity-Sync/Data-Rebuild in progress.

First thing is that it immediately shows the array having 22,6GB of storage used, all being one docker.img

Had about 100GB on the array when it failed, after rebuilding/syncing everything still the only data on the array is that 22GB docker image. Rest of the data is all gone.

 

Any idea what's going wrong? Is it not possible to shrink the array from 2 data drives to 1 data drive?

[garycase]

What you did when you ran "New Config" was essentially setup a new array => which completely invalidated parity, as it recomputed it for the new array.  So you were no longer emulating the contents of the failed drive.

 

What you COULD have done was copy all of the data from the failed drive to the good drive; and THEN done a New Config ... but that's no longer possible.

 

Since you have all of your data still on other drives, the best thing to do is just re-copy it to the array as you've now got it set up.

 

UnRAID does NOT have any provision for "shrinking" an array.  [There are various ways to do this outlined in various forum threads; but there's no built-in way to simply eliminate a drive from the array => and it's not something you'd want to do anyway if you have a failed drive and want to access the data on that drive via emulation.]

 

[Destynx]

Ah I see, I thought I could save the data with this method but I was clearly wrong.

What is this guide about then tho? Cause I presumed that the data could de kept in the array.

https://lime-technology.com/wiki/index.php/Shrink_array

[JorgeB]

Did you read everything?

 

This method does not keep the drive's data within the array. If the drive to be removed has data you want to stay in the array, you must move it yourself to the other data drives. Parity will be built based entirely and only on the remaining drives and their contents.

[Destynx]

You are absolutely right! I did read that part but for some reason I thought that Parity could just be rebuild without that drive.

Fixed it now, created a new array with 1 disk and am putting the data on as we speak. In two days we'll probably add another 2TB and just expand the array, hoping that drive won't fail as quickly. Thank you guys!