I tried to launch an instance and to create volume (from an image) to boot from:
[Tue May 12 14:23:21.682962 2015] [wsgi:error] [pid 30998] error invoking apiclient
[Tue May 12 14:23:21.683017 2015] [wsgi:error] [pid 30998] Traceback (most recent call last):
[Tue May 12 14:23:21.683026 2015] [wsgi:error] [pid 30998] File "/usr/share/op
enstack-dashboard/openstack_dashboard/wsgi/../../openstack_dashboard/api/rest/utils.py", line 114, in _wrapped
[Tue May 12 14:23:21.683033 2015] [wsgi:error] [pid 30998] data = function(self, request, *args, **kw)
[Tue May 12 14:23:21.683040 2015] [wsgi:error] [pid 30998] File "/usr/share/openstack-dashboard/openstack_dashboard/wsgi/../../openstack_dashboard/api/rest/nova.py", line 170, in post
[Tue May 12 14:23:21.683047 2015] [wsgi:error] [pid 30998] new = api.nova.server_create(*args, **kw)
[Tue May 12 14:23:21.683053 2015] [wsgi:error] [pid 30998] File "/usr/share/openstack-dashboard/openstack_dashboard/wsgi/../../openstack_dashboard/api/nova.py", line 586, in server_create
[Tue May 12 14:23:21.683060 2015] [wsgi:error] [pid 30998] meta=meta), request)
[Tue May 12 14:23:21.683066 2015] [wsgi:error] [pid 30998] File "/usr/lib/python2.7/site-packages/novaclient/v2/servers.py", line 907, in create
[Tue May 12 14:23:21.683073 2015] [wsgi:error] [pid 30998] **boot_kwargs)
[Tue May 12 14:23:21.683078 2015] [wsgi:error] [pid 30998] File "/usr/lib/python2.7/site-packages/novaclient/v2/servers.py", line 499, in _boot
[Tue May 12 14:23:21.683085 2015] [wsgi:error] [pid 30998] bdm_dict = {'uuid': image.id, 'source_type': 'image',
[Tue May 12 14:23:21.683091 2015] [wsgi:error] [pid 30998] AttributeError: 'unicode' object has no attribute 'id'
to mention: unchecking "Create new volume" fixes this issue