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Can you tolerate an outage = if a JBOD I/O controller fails? If so, then you don't need dual-port. = But server crashes are more common than JBOD I/O controller failures. = So you should worry more about that. Thank you Alan. Of course you're right, JBOD IO controller is not the first outage = cause, and disks themselves are more prone to fail... I even wonder whether or not dual path is actively used for HDDs, as = dual-port ones are rather hard to find... Not sure then it's really worth it... Of course feel free if I'm wrong / I missed something / one actively = uses it and has some experience / references to share ! Thank you again, Ben