Deleted FlexVol, aggregate won't release the space

[petermiet]

I have an aggregate on a FAS2050 running OnTap 7.3.2 with several 1TB FlexVols on it, and on Friday I deleted one of them to re-create it during some troubleshooting but didn't see the space available. I figured it must have had to process and release (our array is SATA) so I let it go over the weekend and still no additional space freed. Running "aggr show_space" makes me believe that the space is sitting still in WAFL reserve:

Aggregate                       Allocated            Used           Avail

Total space                  9024035984KB    2521786544KB     348701216KB

Snap reserve                          0KB             0KB             0KB

WAFL reserve                 1041451312KB      99056988KB     942394324KB

That's almost 900GB available in reserve! I searched and found suggestions of it being tied up in snapshots or snapshot reserve, but this aggregate has none. I've also been watching "df -Ak" for a while and the numbers to appear to be fluctuating but not by much. Is it really possible that deleting an empty volume can take 3+ days for the space to be returned or is there something else going on?

[nqlcadmin]

I've run that command 4 hours ago and the space hasn't changed   I'll wait till tomorrow and see where it's at. Thanks for your help so far, appreciated.

[nqlcadmin]

So I let it go all night and this morning it has not changed. The wafl scan is just repeating itself and not actually reclaiming any space on the aggr. Out of ideas now.

[johannbell]

Try an aggregate reallocate:

reallocate start -A -o aggr0

[nqlcadmin]

reallocate start -A -o aggr0

Reallocation scan will be started on 'aggr0'.

Monitor the system log for results.

reallocate status aggr0

Reallocation scans are on

aggr0:

        State: Reallocating: block 103261056 of 107002752 (96%)

     Schedule: n/a

     Interval: n/a

Optimization: n/a

Block reallocation scan on aggregate aggr0 is complete.

wafl.reallocate.scan.remove:info]: Reallocation scan for 'aggr0' is being removed.

aggr show_space -g

Aggregate 'aggr0'

    Total space    WAFL reserve    Snap reserve    Usable space       BSR NVLOG           A-SIS

         2449GB           244GB           110GB          2093GB             0GB             7GB

Space allocated to volumes in the aggregate

Volume                          Allocated            Used       Guarantee

vol0                                 25GB             1GB          volume

Aggregate                       Allocated            Used           Avail

Total space                          25GB             1GB           896GB

Snap reserve                        110GB             1GB           108GB

WAFL reserve                        244GB          1189GB             0GB

Still nothing I'll leave it for another night.

[nqlcadmin]

So I finally fixed this in case anyone else out there has this issue. Had exhausted every option and nothing was giving it back.

So get that space back we needed to do:

cf takeover off the other controller, once that failed over, cf giveback and then checked aggr show_space and the space had already started to come back

That's the fix

Thanks.