Tim,  In a greater context a lot of the host based monitoring softwares suffer from this achilles heal when it comes to viewing the array- they really are expecting/looking for a  physicaldisk because thats all the host sees. As far as the host is "aware" the devices in the clariion are direct attach scsi disks the same as the internal drives (except much faster.) It goes out, tries to query the disk and its looking for an actual spinning magnetic disk with a spindle- which it thinks it can find, because the OS is telling it thats what its looking at. Of course, what its really looking at is RAM, and it doesn't have the ability to interpret that memory. By using the array disk based monitoring tools, you can avoid that confusion.  Thanks, Tim
I have a LUN presented from a CX4-480 to an IBM AIX host that is being reported, by the host, as consistently being 99% utilized.  When I look at the Navi Analyzer data, the RAID Group on which the LUN resides, the LUN and the disks all appear to be operating within acceptable parameters.  As an example the maximum utilization for all three areas were as follows for the past week (RG=33%, LUN=14%, disk1=16%, disk2=13%) The LUN is on a RAID 1 RAID Group.  There are other LUNs attached to this same host that do not report high utilization.  Can anyone tell me if AIX or any host operating system, can accurately report the LUN performance?  I would assume the array cache would mask the LUN performance.  Thanks
AIX LUN Performance