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Resizing a LUN to 90% of Flex Volume

Hi

I have 4 CSV LUN's for Hyper-v Cluster.

Each volume is 500 GB (thin provisioned), with a 250 GB LUN with space reservation.

I used to have snapshots of the LUN in the volume, however they are all deleted. What I don't understand is why the volume reports 81% used spaced when there is only 1 LUN of 250 GB. My logic tells me 250 GB of 500 GB should be 50%. What is taking up space from 50% to 81%?

So when i go to my Hyper-v Node, start snapdrive and try to resize, I can't resize to more than 380 GB.

Seems very strange to me... Maybe it has something to do with this Fractional option...

Any help is very appreciated.

/Regards Martin

Re: Resizing a LUN to 90% of Flex Volume

What settings have you got on the volumes for the snapshot reserve and the fractional reserve?

Chris

Re: Resizing a LUN to 90% of Flex Volume

Volume: CSV1

Size: 500GB

Space Setting: None

Fractional Space Reservation: 100%

Deduplication Enabled

LUN: CSV1

Size: 250GB

Space: Reserved

Re: Resizing a LUN to 90% of Flex Volume

Hi,

This is weird.

Normally Fractional Reserve has no impact when a volume is thinly provisioned (guarantee set to none). What's your ONTAP version?

On 7.3.2 (& before) FR setting on a thinly provisioned volume was always forced to 100% (& couldn't be changed), yet space consumption within volume (with existing snapshots) worked like FR was actually set to 0%.

Now I am on 7.3.4 & can change FR to 0%, but even with old (100%) setting it had no impact whatsoever.

Regards,

Radek

Re: Resizing a LUN to 90% of Flex Volume

filer1> version
Data ONTAP Release 7.3.2: Thu Oct 15 04:45:30 PDT 2009

Re: Resizing a LUN to 90% of Flex Volume

Would it help to upgrade to the latest Data OnTAP version?

Re: Resizing a LUN to 90% of Flex Volume

Please, show output of

df -h CSV1

df -r CSV1

Re: Resizing a LUN to 90% of Flex Volume

filer1> df -h /vol/csv1
Filesystem               total       used      avail capacity  Mounted on
/vol/csv1/               500GB      368GB      131GB      74%  /vol/csv1/
/vol/csv1/.snapshot        0KB        0KB        0KB     ---%  /vol/csv1/.snapshots
filer1> df -r /vol/csv1
Filesystem              kbytes       used      avail   reserved  Mounted on
/vol/csv1/           524288000  386486452  137801548 (177292608) /vol/csv1/
/vol/csv1/.snapshot          0          0          0          0  /vol/csv1/.snapshots

Re: Resizing a LUN to 90% of Flex Volume

Do you have any snapshots on this volume (snap list csv1)?

Do you have de-duplication enabled for csv1?

Re: Resizing a LUN to 90% of Flex Volume

filer1> sis status /vol/csv1

Path                           State      Status     Progress
/vol/csv1                      Enabled    Idle       Idle for 118:56:06

filer1> snap list csv1

Volume csv1

working...

No snapshots exist.