Dumb Volume/Dataset Question

[Stanri010]

So I've got a very dumb question that I've been struggling with. I've been trying to figure out if I understand this correctly. Correct me if I'm wrong please.

I have a volume created that has the capacity of 16.2TB and within that volume, I've got a Dataset called "Vault" (which is the one I've got mapped in windows) and within that dataset I've got four data sets: Archive, BT Sync, Media, and Jails.

1)Assuming that's correct, where exactly did 1.9 TB worth of space disappear off to between the 3.7TB used and 5.6TB used from 16.2?

2) How come a drive mapped with windows wont show the correct used capacity when you have a dataset inside the mounted and mapped drive? ie. 3.7 TiB used shown in Freenas but only 2.39 TB shown in windows?

 

[dlavigne]

Did you figure this out?

 

[Stanri010]

Not at all. The only thing I've seen is the mention of TiB is different from TB but it doesn't seem to correlate since Freeness says I've got 10.3 TiB free while windows says I've also got 10.3 TB free.

My issue is the 3.7 TiB used for Vault but then it says I've got 5.6TiB used for the entire volume.

 

[danb35]

@Stanri010, forum rules ask that you specify FreeNAS version and hardware, and both would be relevant to this discussion. I'm going to guess that you're running FreeNAS 9.3, since that version seems to have changed the way that volume and dataset capacity are reported. In short, the volume capacity is shown "raw", i.e., the total capacity of all disks that comprise the pool. Dataset capacity is shown "net", i.e., with the parity drives subtracted. A RAIDZ2 pool consisting of 6 x 4 TB disks would have a raw capacity of 24 TB (~21.6 TiB), but a net capacity of 16 TB (~14.4 TiB). Amounts used and free will do the same thing.

From the values you've posted, it looks like you've got either a 3-disk RAIDZ1 pool, or a 6-disk RAIDZ2 pool.

 

[Stanri010]

I see. Thanks for clearing that up for me. As you said I am on 9.3 and have 6x 4tb in a ridz2. It's strange that volume and and dataset have different ways of reporting available space.

It's just according to that first image board, I have 3.7TiB used and 10.3TiB free = 14TiB total for the dataset but 16.2 TiB for the volume after raidz2. I guess its just the way it's reported that you said that accounts for almost 2TiB missing?

Alternatively, it's mislabled as TiB instead of TB. That would make sense too.

 

[danb35]

The image you posted shows 5.6 TiB used and 16.2 TiB available for the volume, for a total of 21.8 TiB. The dataset shows 3.7 TiB used and 10.3 TiB available, for a total of 14 TiB. You'll notice that both of those are very close to the numbers I mentioned above.

The Web UI is reporting capacities in TiB (2^40 bytes), while drive manufacturers spec them in TB (10^12 bytes). If you were expecting to see 16 TB capacity in the UI, but are only seeing 14, that's the reason.

 

[Stanri010]

Thanks, that answers my question