This problem has been raised before, probably the same solution applies here. If you are deploying the vVNX using the vSphere client, deploy it using the webclient. Good change that everything will work.
Does anybody face the same issue? When turning on vVNX running on vSphere 5.5, it always boots up in service mode. We can ssh to the vVNX with ID/Password = service/service. We cannot use userID="admin" for Unisphere GUI access but only "service" (which is automatically set in the Unisphere log-in screen).  Since it always boots up in service mode, we checked SECURE MODE bit by "svc_rescue_state -l" but no SECURE MODE bit was set...  If anybody has the same issue and knows how to fix it, please share the information to us!
vVNX boots up in service mode (only)