Attaching volume to iso instance is failure because of duplicate device name 'hda'

Issue

• Boot instance from ISO image and try to attach cinder volume to the instance. The nova volume-attach command will succeed. But, the operation will fail with following error(nova-compute.log):

[root@controller ~(keystone_admin)]# nova volume-attach rhel7_boot_from_iso 12be458a-a40c-43a8-b87b-33b3eaadc2f9 
+----------+--------------------------------------+
| Property | Value                                |
+----------+--------------------------------------+
| device   | /dev/hda                             |
| id       | 12be458a-a40c-43a8-b87b-33b3eaadc2f9 |
| serverId | 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba |
| volumeId | 12be458a-a40c-43a8-b87b-33b3eaadc2f9 |
+----------+--------------------------------------+

2015-08-17 19:48:00.569 19970 DEBUG nova.volume.cinder [req-05281bfc-8c50-4d18-b060-bd6756a5a016 None] Cinderclient connection created using URL: http://192.168.100.10:8776/v1/d3979f95e8c144e8a7936202a42f929e get_cinder_client_version /usr/lib/python2.7/site-packages/nova/volume/cinder.py:255
2015-08-17 19:48:00.669 19970 ERROR nova.compute.manager [req-05281bfc-8c50-4d18-b060-bd6756a5a016 None] [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba] Failed to attach 12be458a-a40c-43a8-b87b-33b3eaadc2f9 at /dev/hda
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba] Traceback (most recent call last):
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 4606, in _attach_volume
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     do_check_attach=False, do_driver_attach=True)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/virt/block_device.py", line 46, in wrapped
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     ret_val = method(obj, context, *args, **kwargs)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/virt/block_device.py", line 261, in attach
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     connector)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/openstack/common/excutils.py", line 82, in __exit__
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     six.reraise(self.type_, self.value, self.tb)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/virt/block_device.py", line 252, in attach
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     device_type=self['device_type'], encryption=encryption)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/virt/libvirt/driver.py", line 1426, in attach_volume
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     self._disconnect_volume(connection_info, disk_dev)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/openstack/common/excutils.py", line 82, in __exit__
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     six.reraise(self.type_, self.value, self.tb)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/nova/virt/libvirt/driver.py", line 1415, in attach_volume
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     virt_dom.attachDeviceFlags(conf.to_xml(), flags)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 183, in doit
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     result = proxy_call(self._autowrap, f, *args, **kwargs)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 141, in proxy_call
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     rv = execute(f, *args, **kwargs)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 122, in execute
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     six.reraise(c, e, tb)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 80, in tworker
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     rv = meth(*args, **kwargs)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]   File "/usr/lib64/python2.7/site-packages/libvirt.py", line 524, in attachDeviceFlags
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba]     if ret == -1: raise libvirtError ('virDomainAttachDeviceFlags() failed', dom=self)
2015-08-17 19:48:00.669 19970 TRACE nova.compute.manager [instance: 2e2a7ce5-6e4f-43f6-acac-b2270755b1ba] libvirtError: Requested operation is not valid: target hda already exists