Uses the following OIDs, the math that has to be done is explained in the OIDs. Use Raw Data for history trending. I also think that when the SAN is rebooted/loses power the values reset to 0, unsure though.
cpqDaPhyDrvHReads
cpqDaPhyDrvHWrites
cpqDaPhyDrvReads
cpqDaPhyDrvRefHours
cpqDaPhyDrvWrites
