DFM Agg Used Size vs. Physical Used Size

The following graphs are from Operations Manager 3.8

Is there a resource or document that explains the values in the graphs below. I am trying to determine the difference in the aggregate "used" column

of the Aggregate Space Availability graph from the aggregate "Physical Used" space in the column of the Aggregate Space Savings graph.

I need to know why the aggregate used space is different than the aggregate physical used space. I need to provide an explanation as to why the total aggregate

size (excluding aggr0) used in graph 1 does not add up to the physical size used in graph 2.

All help is greatly appreciated.

Thanks in Advance

Re: DFM Agg Used Size vs. Physical Used Size


"Used" is the capacity usage of the aggregate as reported by ONTAP "df" command.

"Physical Used" is calculated by DFM as the sum of "Physical Used" of all ASIS volumes. You can check the sum by clicking on the aggregate name in this report, then in the aggregate details jump to the Volumes link then open the "Volume Dedupe ..." report.

I think the two will differ if some non ASIS volumes exist on the aggregate, can you pls check if that's the case.



Re: DFM Agg Used Size vs. Physical Used Size


All volumes in all the aggregates have ASIS enabled.

I can see how the physical space is calculated by the following. The following is for aggr1 and all the volumes that exist in aggr1.

Aggr1 Physical Used Space



Filesystem                used       compressed         a-sis     %saved

/vol/vditemplate01/   28196880                0     248569848        90%

/vol/vdids3PCC/      810128928                0    4108791268        84%


Filesystem              kbytes       used      avail capacity  Mounted on

/vol/vditemplate01/  209715200   28196880  181518320      13%  /vol/vditemplate01/

/vol/vditemplate01/.snapshot          0          0          0     ---%  /vol/vditemplate01/.snapshot

/vol/vdids3PCC/     1610612736  810128928  800483808      50%  /vol/vdids3PCC/

/vol/vdids3PCC/.snapshot          0          0          0     ---%  /vol/vdids3PCC/.snapshot

There is no snapshot for the volumes that are in aggr1

===== SNAP-LIST-N =====

Volume vditemplate01


No snapshots exist.

Volume vdids3PCC


No snapshots exist.

Total Aggregate Physical Space: 799GB

However, I do not see how the physical space form the df -s and df commands add up to the used space in the aggregate from the df -A

command. IF you include the aggregate snapshot used space of 263 to the above aggregate physical total of 799 you get 1.061 TB which is not

depicted in the Aggregate Space Availability graph which shows 1.02 TB used.

Aggregate Used Space


df -A

Aggregate               kbytes       used      avail capacity

aggr1               5238716824 1095885552 4142831272      21%

aggr1/.snapshot      275721936  118478352  157243584      43%

Hope this makes sense.

Thanks for the help!