ZFS disk usage vs. VM disk size

Mrt12

Well-Known Member
May 19, 2019
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Hi all,
I thought I mastered the understanding of how ZFS reports disk usage, but I was wrong :-)
I have a VM that has a disk having a size of 6TB:

1622640580382.png

6010GB, to be exact. This VM is, together with others, on a server having a 16TB raidz-2. And the weird thing is that this morning I got an email report from my server about my 16TB disk being full! and I totally don't understand why. Yes there are other VMs, but none of the others is as large as this one:

1622640684816.png

1622640745482.png

Yes, there are also snapshots, but I deleted all of them for the 6TB disk (however, ZFS autosnap keeps creating new ones):

1622640810667.png

so what I don't understand is why the vm-104-disk-1 can have a size of 8 TB when I have actually configured it to be 6 TB.
Also I don't understand why my 16 TB disk is almost full (95%) - I have a couple of VMs, but all of them are only Mickey Mouse size compared to this 6TB one:

1622641026634.png

So where has my disk space gone? I really cannot understand. I hope someone can clarify things a bit!

Thanks in advance for any hints :-)
 

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Parity, metadata, ... Could you please also post the following output?
Code:
zpool list
zfs get all tank

You can also try some ZFS capacity calculator, for example https://wintelguy.com/zfs-calc.pl