Hi dkmartin,

From the way you describe the layout, I'm going to assume that you're running something like SVC for the management of the LUN's. Are the AIX environment LPAR's or are they standalone machines, or something else of course.

Managing LUN's accross six individual SAN devices is very costly in resource, along with the planning headache when it comes to new system builds - well inless you have plenty of disk. I currently have two devices - a 1.5Pb VMax and a 250Gb VNX and that provides enough confusion.

Where ver possible our approach is to go for a single LUN, but we do have quite a number of systems with large numbers of luns (some are in excess of 200) on AIX, Solaris and RHEL. We do have some very old versions on VMware, but they are slowly being decommissioned.

So in reality I would if time permits look at load and I/O on a system by system basis, where the results indicate there would be a benefit - replicate the existing model. If the results show it would be OK, go for the single LUN, if you're using Metro or Global mirror you may have to delve a bit deeper and look at inter system bandwidth.

Regards

Gull04