This feature of Operations Manager has vexed me for a long while so its open season for the smart people out there to help me out
I'm going to keep this example simple and concentrate on the spare disk capacity reported on one system however I get equally baffling numbers for data and parity capacity count:
From the Operations Manager server run 'dfm physical summary <hostname>'
I get the following output relating to spare disks:
Spare Disks: 2
Spare Space: 1174841327616
If I look at the sysconfig -r output from the Filers console (I'm using 600GB FC drives here):
Spare disks
RAID Disk Device HA SHELF BAY CHAN Pool Type RPM Used (MB/blks) Phys (MB/blks)
--------- ------ ------------- ---- ---- ---- ----- -------------- --------------
Spare disks for block or zoned checksum traditional volumes or aggregates
spare 0a.61 0a 3 13 FC:A - FCAL 15000 560000/1146880000 560208/1147307688
spare 0a.77 0a 4 13 FC:A - FCAL 15000 560000/1146880000 560208/1147307688
The Operations Manager is reported in KB and the ONTAP output in MB. Assuming 1024 is used for MB to KB conversion then the two figures on interest are:
Raw: 560208*1024*2 (Physical size x MB to KB x number of disks) = 1147305984
Useable (right sized): 560000*1024*2 (Used size x MB to KB x number of disks) = 1146880000
Neither of these two results match the spare space output reported by Operations Manager.
Any know how OM is deriving its answer and why is it different from ONTAP?
Forgot to add some details:
OM version 3.8.1
ONTAP version 7.3.3