First expansion, not the space I expected

[dalbright]

Been with this ReadyNAS fro about 4 years, first time posting...

I performed my first Xraid expansion yesterday, swapping a 2TB drive with a 4TB drive, however, my expanded RAID is not fully utilizing the new drive. Details below:

Prior to expansion, my ReadyNas Ultra 4 plus config was:
Drive 1: WD RED 2TB - 1863 GB - 1858GB Allocated
Drive 2: WD RED 2TB - 1863 GB - 1858GB Allocated
Drive 3: WD RED 3TB - 2794 GB - 2790GB Allocated
Drive 4: WD RED 3TB - 2794 GB - 2790GB Allocated


Yesterday, i replaced Drive 1 with a 4TB WD RED drive and the device executed the restriping and expansion, but drive one is maxed out at 2790 GB allocated (despite drive size of 3726 GB). It now looks like:

Drive 1: WD RED 4TB - 3726 GB - 2790GB Allocated
Drive 2: WD RED 2TB - 1863 GB - 1858GB Allocated
Drive 3: WD RED 3TB - 2794 GB - 2790GB Allocated
Drive 4: WD RED 3TB - 2794 GB - 2790GB Allocated

Does anyone have any inisght into why the 4GB drive is being treated identically to a 3GB drive?

Firmware vs is up to date, RAIDiator 4.2.31.

Thanks!

[mdgm-ntgr · Accepted solution]

You'll need to replace another disk with a 4TB one to get further vertical expansion.

Note that expansion is limited to 8TB over the life of the volume and you cannot expand past 16TB.

[mdgm-ntgr · Accepted solution]

You'll need to replace another disk with a 4TB one to get further vertical expansion.

Note that expansion is limited to 8TB over the life of the volume and you cannot expand past 16TB.

[Retired_Member]

You could use the Netgear RAID calculator to see in detail what is going on.

Please follow the link

http://rdconfigurator.netgear.com/raid/index.html

[StephenB]

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@mdgm wrote:

You'll need to replace another disk with a 4TB one to get further vertical expansion.

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Correct. The capacity rule for single redundancy is pretty simple - sum the disks and subtract the largest.  

In addition to the two volume size constraints @mdgm-ntgr mentioned, the new disks need to be at least as large as the largest already installed.

[dalbright]

Ok, thanks everyone.  I have another 4fb standing by, but didn't want to add it if the space was going to be wasted.  Appreciate the feedback!

[mdgm-ntgr]

Replacing the remaing 2TB disk with a 4TB disk would get you about 2TB (approx 1.8TiB) of vertical expansion.

[dalbright]

The hatbwork d!  Thanks for The advice!