How to clear unused iscsi device after replace

Question

I just use new iscsi disk to replace old iscsi disk on Ubuntu 14.04. I had mount new, migrate data and replace mount point(/var/vcap/store). But old iscsi target was still existing.

colocated/1a24af4c-ad6a-4ac8-b3d4-c17e64397be4:/var/vcap/bosh_ssh/bosh_dd4aa9f0a6194c1# dmsetup ls
3600a09803830374d763f4a314a6e4544-part1 (252:3)
3600a09803830374d782b4a4445544176   (252:0)
3600a09803830374d782b4a4445544176-part1 (252:1)
3600a09803830374d763f4a314a6e4544   (252:2)

colocated/1a24af4c-ad6a-4ac8-b3d4-c17e64397be4:/var/vcap/bosh_ssh/bosh_dd4aa9f0a6194c1# df -h
Filesystem                                           Size  Used Avail Use% Mounted on
udev                                                 3.9G  4.0K  3.9G   1% /dev
tmpfs                                                802M  200K  802M   1% /run
/dev/xvda1                                           2.9G  1.2G  1.6G  44% /
none                                                 4.0K     0  4.0K   0% /sys/fs/cgroup
none                                                 5.0M     0  5.0M   0% /run/lock
none                                                 4.0G     0  4.0G   0% /run/shm
none                                                 100M     0  100M   0% /run/user
/dev/xvdc2                                            91G   84M   86G   1% /var/vcap/data
tmpfs                                                1.0M     0  1.0M   0% /var/vcap/data/sys/run
/dev/mapper/3600a09803830374d763f4a314a6e4544-part1   20G   44M   19G   1% /var/vcap/store

colocated/1a24af4c-ad6a-4ac8-b3d4-c17e64397be4:/var/vcap/bosh_ssh/bosh_dd4aa9f0a6194c1# multipath -ll
3600a09803830374d782b4a4445544176 dm-0 NETAPP  ,LUN C-Mode
size=40G features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=0 status=enabled
| `- 14:0:0:177 sde  8:64    failed faulty running
`-+- policy='round-robin 0' prio=0 status=enabled
`- 15:0:0:177 sdc  8:32    failed faulty running
3600a09803830374d763f4a314a6e4544 dm-2 NETAPP  ,LUN C-Mode
size=20G features='1 queue_if_no_path' hwhandler='0' wp=rw
|-+- policy='round-robin 0' prio=4 status=active
| `- 12:0:0:4   sdd  8:48    active ready  running
`-+- policy='round-robin 0' prio=1 status=enabled
`- 13:0:0:4   sda  8:0     active ready  running

For example, I want to delete 3600a09803830374d782b4a4445544176 iscsi as showed above.