RHEL6. STK6580_6780 multipathd.

STK6580_6780 uses rdac driver to organize proper multipathing. Rdac drivers are inbuilt in to the rhel6 kernel as module scsi_dh_rdac, no need to build it from third-party source.

multipath.conf

defaults {
        udev_dir                /dev
        polling_interval        5
        path_grouping_policy    failover
        rr_min_io               1000
        rr_weight               uniform
        find_multipaths yes
        user_friendly_names yes
}
devices {
         device {
             vendor                  "SUN"
             product                 "STK6580_6780"
             features                "2 pg_init_retries 50"
             hardware_handler        "1 rdac"             
             path_grouping_policy    group_by_prio
             path_selector           "round-robin 0"
             prio                    rdac
             path_checker            rdac
             failback                10
             no_path_retry           30
             rr_min_io               100
         }
}
blacklist {

}

Next step is to properly configure filter in lvm.conf. My fileter is

filter = [ "a|/dev/cciss/.*|", "a|/dev/mapper/mpath.*|", "r|.*|" ]

Also you can add string modprobe scsi_dh_rdac in /etc/rc.modules
[root@stor01 ~]# cat /etc/rc.modules 
modprobe scsi_dh_rdac