Aggregate size question

Hi everyboby,

i have a little question about aggregate sizing. I have a aggregate called aggr1 consisting of 24 disks â 137 GB hosted on a FAS920c running Ontap 7.0.1R1.

As i have 2 raidgroups 4 disks are parity. I took the 20 left disks and calculated the following:

20 (disks) x 137 GB (size) x 0,90 (10% WAFL) x 0,95 (5% Aggr Snapshot) = 2342,7 GB

When i perform a 'df -Ahr' i only see this:

df -Ahr Aggregate total used avail reserved aggr1 2270GB 1924GB 346GB 0GB aggr1/.snapshot 119GB 34GB 84GB 0GB

So i have a difference of about 70 GB between my result and the total which Ontap shows me. Ok, 70 GB won't make the world turn faster :-) but i would like to understand why i am missing 70 GB.

Thanks in advance

Jochen