Yes . No of enclosures on one Backend loop is 8.  You should distribute the DAEs across Backend BUSes evenly for improved performance, .Hope the below link will be helpful for you.  [URL]  The primus solution emc28236 also explains how to add new DAE to existing configuration. You may refer the below best practice guide in creating RGs and LUNs on new Enclosures.  White Paper: EMC CLARiiON Storage System Fundamentals for Performance and Availability — Applied Best Practices  Vipin V.K
Hi All! As I know FC-AL may contain maximum 128 devices. As per as drive module is single device, i think that one back-end loop may contain 8 enclosures (15*8=120). Am I correct? The next question is that I`m about to add 12 enclosures at CX4-960. I will use USM. That is my action plan: 1. Install DAEs in the rack 2. Power up DAEs 3. Manually set up enlosure IDs 4. Connect enloserus one after another via USM.  Any recomendations or advises?  Also I will be glad to get any links to documets dealed with questions above.  Best regards, Alex T.
Maximum enclosures per loop