LS441DE - Unable to join new disk to an array?

[ntracing]

My LS441DE had a disk that stopped booting.  Put in a new disk of the same type, but the software does not seem to allow me to add the new drive to the degraded array?

I did notice that the new drive formatted with slightly lower "unit capacity"  Disk 3 (Still in Array 5573.8GB) new Disk 4 (5571.6GB)...  Both drives are: ST6000VN0033-2EE

When I go to RAID array list, Array 2 RAID1 is in Degraded state with only one drive, when I click into the array, I get an error "Not enough drives are selected"... ok, but it will NOT let me select the new Disk 4 that is in the system.  I assumed I would just select the new disk and hit "Recover RAID Array" (currently greyed out button), and all would be well.

Any ideas why I can not add this drive to the array?  Recommendations to fix?  Hoping I don't need to rebuild from scratch as it is days of copying data.

Thanks!

[1000001101000]

Hopefully someone with more experience with the web ui will answer in detail...

But I think you need to delete the filesystem you just created on that drive before you add it to your array. I think the manual probably has the procedure, I believe you need to initialize it but not format it or something like that.

[Texturtle]

You'll need to delete the file system from the drive and redo it. When using drives of the same size the only way it usually have enough capacity to join the RAID is to do it without formatting, just recover the RAID array with an unformatted drive.

Follow the steps in this KB article to remove the file system. I know it says Windows 7, but the same procedure will work with 8 or 10 as well.

https://www.buffalotech.com/knowledge-base/cleaning-a-disk-in-windows-7-using-diskpart