DSM 7.0 DS920 newly added 3rd drive has not expanded the volume !

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DSM 7.0 DS920 newly added 3rd drive has not expanded the volume !

DS920+ DS214Play DS212+
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I have a DS920+. Installed 2 x 12TB wd’s. Then I decided to add another. All accounted for after 3 days of whatever the system was doing.

The Storage Pool shows 21.8 TB, but Volume 1 (the only volume ) still shows 10.5GB. So now I have 3 bays filled, but still only 10.5GB is showing in the pool as opposed to say 21 TB.

It may be obvious to some, but what is it I’m missing ?
Thanks Telos ... been through these suggestions ... it's a single pool, single volume created on a DS418Play (capable of 108 TB pool), migrated to another DS418Play with more capacity ... none of the expansion options (automatic or manual) seem to be on offer.
"The maximum single volume size is determined when the volume is created. Therefore, migrating your drives from a Synology NAS supporting 16 TB to another Synology NAS supporting 108 TB does not mean the maximum single volume size will expand from 16 TB to 108 TB. " ... this seems to infer it's to do with the capabilities of the NAS, but as Rusty suggests, it might just be baked in ...
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I have a DS920+ and am on DSM 6.2.4-25556 Update 6. I upgraded from 4x4TB drives to 2x8TB and 2x4TB drives. I did the repair thing (replaced drives and repaired one at a time) and storage pool 1 shows healthy as well as all four drives. Problem is the total capacity shows only 6.98 TB. The RAID calculator shows it should be 16TB with SHR raid config (RAID Calculator | Synology Inc.). The "convert a single-volume" to "multiple-volume" option is not available (see Capture 1.png below). And the configure action under volume menu doesn't seem to allow me to increase max size (capture 2.png). Thoughts on how to fix so I can use all 16TB? Thanks


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Thanks for the quick reply. Thoughts on the best way to fix this? Is there any way to increase volume size at this point? Or do I need to transfer data to a different NAS and try starting from scratch on this one? Thanks

- also got the model # wrong above. It is a DS918+ Not sure if that makes a difference
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