Multipath

yum install device-mapper-multipath

/dev/mapper/mpathN

mpathconf --enable --user_friendly_names y

blacklist {     
  devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"     
 }

defaults {
...
        find_multipaths yes
...
}

rescan-scsi-bus.sh

cd /dev/disk/by-id/
ls -lthr

grep scsi-xxxxxxxxxxxxxxxxxxx-part1

devices {
    device {
    vendor "COMPELNT"
    product "Compellent Vol"
    features "0"
    hardware_handler "0"
    prio "const"
    no_path_retry 24
    path_grouping_policy "multibus"
    path_checker "tur"
    failback immediate
    rr_weight "uniform"
    fast_io_fail_tmo 5
    dev_loss_tmo infinity
    path_selector "round-robin 0"
    }
}

multipaths {
    multipath {
    wwid 36000d310042cbc000000000000000004
    alias  DATA_01
    features "1 queue_if_no_path"
    }
}

defaults {
    no_path_retry    fail
    find_multipaths yes
    user_friendly_names yes
    polling_interval 5
}

DATA_01 should be ASM name

multipath -ll

mpatha (36000d310042cbc000000000000000004) dm-2 COMPELNT,Compellent Vol
size=500G features='1 queue_if_no_path' hwhandler='0' wp=rw
`-+- policy='service-time 0' prio=1 status=active
  |- 7:0:0:1  sdb 8:16 active ready running
  |- 7:0:2:1  sdc 8:32 active ready running
  |- 16:0:0:1 sdd 8:48 active ready running
  `- 16:0:2:1 sde 8:64 active ready running