Multipath configuration

Red Hat Enterprise Linux 4 Update 4 does not include a default multipath configuration for the system.

You must update the device part of your multipath.conf as follows:
  device {
                vendor                  "IBM "
                product                 "2145"
                path_grouping_policy    group_by_prio
                prio_callout            "/sbin/mpath_prio_alua /dev/%n"
                features                "1 queue_if_no_path"
                path_checker            tur
        }