Removing Luns

You need to remove the mpath device and the associated scsi devices

 [root@dubl5oradbng02 ~]# multipath -ll | grep -i -A12 60002AC00000000000005AA900025DF3
mpathx (360002ac00000000000005aa900025df3) dm-44 3PARdata,VV
size=2.4T features='1 queue_if_no_path' hwhandler='1 alua' wp=rw
`-+- policy='service-time 0' prio=50 status=active
  |- 1:0:6:19 sdeu 129:96  active ready running
  |- 1:0:5:19 sdev 129:112 active ready running
  |- 1:0:7:19 sdex 129:144 active ready running
  |- 1:0:4:19 sdew 129:128 active ready running
  |- 3:0:7:19 sdfc 129:224 active ready running
  |- 3:0:5:19 sdfe 130:0   active ready running
  |- 3:0:4:19 sdfd 129:240 active ready running
  `- 3:0:6:19 sdff 130:16  active ready running
mpathk (360002ac00000000000000d7300025df4) dm-38 3PARdata,VV

You need to remove EVERYTHING

 multipath -ll -f mpath 

This will remove the mpath device but your scsi devices remain

 echo 1 > /sys/block/sdet/device/delete 
 partprobe #this will rescan the scsi bus 
   echo "1" > /sys/class/fc_host/host3/issue_lip
   echo "1" > /sys/class/fc_host/host1/issue_lip
   # THese 2 will scan the hbas
   

At this point you have cleared all devices associated with the mpath device and rescanned. If you have changed the name it should now be visible with the new name.

Troubleshooting

use

 lsblk 

to check if you see a scsi device that you believe is a san device that is not associated with an mpath

sdfe                        130:0      0   2.5T  0 disk
└─mpathx                    252:44     0   2.5T  0 mpath

then chances are its one that you forgot to remove

Also as a finale fix a reboot will in most cases make life easier but in case it can not be done