The figure given by the Snapshot reserve used (GB) metric of the NetApp Plugin in Oracle Enterprise Manager appears to be wrong.
For example, we have a volume whose snapshot reserve metrics in OEM claim to be:
Snap reserve info > reserve used (GB): 22.4
Snap reserve info > reserve total (GB): 522.2
Snap reserve info > reserve used (%): 4.3
Doing a Unix df on the volume gives:
Filesystem total used available capacity
vol/xxxxx/.snapshot 522GB 354GB 167GB 68%
The df gives figures we would expect given the snapshots we know to be in there, suggesting the OEM figures are wrong.
Any advice would be gratefully received.