Replacing 4tb with 14tb drives expanding SHR1

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Replacing 4tb with 14tb drives expanding SHR1

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Easiest way to check is to attempt to add any smaller drive - you don't have to continue the ADD just see if it gives you a message when attempting the ADD - then cancel. On my 5 x 14 TB SHR1 if I attempt to add a 3 TB drive, I get a message telling me it can't be done.

I get the following attempting to add a 3TB drive (don't have any 4TB) to my 5x14TB SHR1:

Click the link (1 drive) in the message below...

and get this...


From Synology:
Do the following according to your DSM version:
  • DSM 7 and above:
    1. Go to Storage Manager > Storage and select the SHR storage pool you want to add drive to.
    2. Click the
      icon and select Add Drive.
  • DSM 6.2 and below:
    1. Go to Storage Manager > Storage Pool and select the SHR storage pool you want to add drive to.
    2. Click Action and select Add Drive.

How do I expand the storage capacity of SHR?

You can expand the storage capacity of an SHR storage pool by either replacing existing drives with ones of a larger size or adding additional drives.
I’m not sure there was much more to add to this thread since the Knowledgebase is very clear on expanding a pool or replacing drives in a pool. I linked to this in my earlier post: Replacing 4tb with 14tb drives expanding SHR1

The only confusion could be from Synology’s online RAID sizing tool. That’s only correct when creating a new storage pool. If you want to work on an existing storage pool then go into Storage Manager and click the ‘?’ icon to read the help.
So that nas of mine currently has two 4tb drives and two 14tb drives. I wonder if it would let me add the other two 4tb back (4x4tb 2x14tb but in this order 4,4,14,14,4,4)
Again, while most of you seem to have known this, and the logic is there, it never dawned on my this would not be an option. I learned something from this discussion.
It is correct. SHR expand does not support adding smaller drives then the current largest drive in the array.
Apologies for addressing an older article, but I just wanted to confirm this with an empirical observation. When I first started with my DS1019+, I had a mix of 2x 4TB, 1x 3TB and 2x2TB drives in the array. At one stage, I tried to substitute one of the 2TB for another 3TB drive, but was only able to use 2TB of this drive.

So you can replace a HDD with one of equivalent capacity or with a drive matching (or exceeding) the largest capacity drive in the array, but adding a drive with a size between the the two will not provide you with any extra storage capacity.

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