We have an HP XP12000 SAN with 450 Tb of data, with multiple types of RAID config. We want to reduce the size of the SAN, which we see as happening in two ways: a. Reduce RAID 5 to a lower but still resilient level and b. Trawl through the data remove duplicates etc. Two questions - a. What is an optimal resilience level? and b. What tools (SW etc) are available to manage and control data? FYI - we use SAP R/3 and BW with CRM coming soon. We also have an very active web site.