I'm using Juno, Ubuntu 14, vsphere 5.5. and VMwareVCDriver. Cinder services are running but when I tried to create one volume, it fails with (cinder-api.log):

 CinderException: Failed to create api volume flow

When I checked the rest of the log files, there was the following message every few minutes:

WARNING cinder.volume.manager [-] Unable to update volume replication status, VMwareVcVmdkDriver -1.3.0  driver is uninitialized.

And when cinder-volume is restarted, the log shows:

ERROR suds.client
...
Error encountered during initialization of driver: VMwareVcVmdkDriver
...
Exception: (503, u'Service Unavailable')

My cinder file is:

rpc_backend = rabbit
rabbit_host = controller
rabbit_password = *****
my_ip = 192.168.104.42
verbose = True
debug = True

volume_driver=cinder.volume.drivers.vmware.vmdk.VMwareVcVmdkDriver
vmware_host_ip = 192.168.104.40
vmware_host_username = root
vmware_host_password = ****
vmware_wsdl_location = file:///opt/vmware/SDK/vsphere-ws/wsdl/vim25/vimService.wsdl

rootwrap_config = /etc/cinder/rootwrap.conf
api_paste_confg = /etc/cinder/api-paste.ini
iscsi_helper = tgtadm
volume_name_template = volume-%s
volume_group = cinder-volumes
verbose = True
auth_strategy = keystone
state_path = /var/lib/cinder
lock_path = /var/lock/cinder
volumes_dir = /var/lib/cinder/volumes

[database]
connection = mysql://cinder:*****@controller/cinder

[keystone_authtoken]
auth_uri = http://controller:5000/v2.0
identity_uri = http://controller:35357
admin_tenant_name = service
admin_user = cinder
admin_password = ****

[DEFAULT]
glance_host = controller