diff --git a/magnum/common/exception.py b/magnum/common/exception.py
index e2f7310e9b..dfda3c4568 100644
--- a/magnum/common/exception.py
+++ b/magnum/common/exception.py
@@ -331,6 +331,14 @@ class FileSystemNotSupported(MagnumException):
                 "File system %(fs)s is not supported.")
 
 
+class BayModelNotFound(ResourceNotFound):
+    message = _("Baymodel %(baymodel)s could not be found.")
+
+
+class BayModelAlreadyExists(Conflict):
+    message = _("A baymodel with UUID %(uuid)s already exists.")
+
+
 class BayNotFound(ResourceNotFound):
     message = _("Bay %(bay)s could not be found.")
 
diff --git a/magnum/db/api.py b/magnum/db/api.py
index fc15520174..fcb7ede0f7 100644
--- a/magnum/db/api.py
+++ b/magnum/db/api.py
@@ -169,32 +169,6 @@ class Connection(object):
         :returns: A list of tuples of the specified columns.
         """
 
-    @abc.abstractmethod
-    def reserve_baymodel(self, tag, baymodel_id):
-        """Reserve a baymodel.
-
-        To prevent other ManagerServices from manipulating the given
-        BayModel while a Task is performed, mark it reserved by this host.
-
-        :param tag: A string uniquely identifying the reservation holder.
-        :param baymodel_id: A baymodel id or uuid.
-        :returns: A BayModel object.
-        :raises: BayModelNotFound if the baymodel is not found.
-        :raises: BayModelLocked if the baymodel is already reserved.
-        """
-
-    @abc.abstractmethod
-    def release_baymodel(self, tag, baymodel_id):
-        """Release the reservation on a baymodel.
-
-        :param tag: A string uniquely identifying the reservation holder.
-        :param baymodel_id: A baymodel id or uuid.
-        :raises: BayModelNotFound if the baymodel is not found.
-        :raises: BayModelLocked if the baymodel is reserved by another host.
-        :raises: BayModelNotLocked if the baymodel was found to not have a
-                 reservation at all.
-        """
-
     @abc.abstractmethod
     def create_baymodel(self, values):
         """Create a new baymodel.
@@ -251,7 +225,6 @@ class Connection(object):
 
         :param baymodel_id: The id or uuid of a baymodel.
         :returns: A baymodel.
-        :raises: BayModelAssociated
         :raises: BayModelNotFound
         """
 
diff --git a/magnum/db/sqlalchemy/api.py b/magnum/db/sqlalchemy/api.py
index 98fa0a872c..b2591b7b37 100644
--- a/magnum/db/sqlalchemy/api.py
+++ b/magnum/db/sqlalchemy/api.py
@@ -340,44 +340,6 @@ class Connection(api.Connection):
         return _paginate_query(models.BayModel, limit, marker,
                                sort_key, sort_dir, query)
 
-    def reserve_baymodel(self, tag, baymodel_id):
-        session = get_session()
-        with session.begin():
-            query = model_query(models.BayModel, session=session)
-            query = add_identity_filter(query, baymodel_id)
-            # be optimistic and assume we usually create a reservation
-            count = query.filter_by(reservation=None).update(
-                        {'reservation': tag}, synchronize_session=False)
-            try:
-                baymodel = query.one()
-                if count != 1:
-                    # Nothing updated and baymodel exists. Must already be
-                    # locked.
-                    raise exception.BayModelLocked(baymodel=baymodel_id,
-                                               host=baymodel['reservation'])
-                return baymodel
-            except NoResultFound:
-                raise exception.BayModelNotFound(baymodel_id)
-
-    def release_baymodel(self, tag, baymodel_id):
-        session = get_session()
-        with session.begin():
-            query = model_query(models.BayModel, session=session)
-            query = add_identity_filter(query, baymodel_id)
-            # be optimistic and assume we usually release a reservation
-            count = query.filter_by(reservation=tag).update(
-                        {'reservation': None}, synchronize_session=False)
-            try:
-                if count != 1:
-                    baymodel = query.one()
-                    if baymodel['reservation'] is None:
-                        raise exception.BayModelNotLocked(baymodel=baymodel_id)
-                    else:
-                        raise exception.BayModelLocked(baymodel=baymodel_id,
-                            host=baymodel['reservation'])
-            except NoResultFound:
-                raise exception.BayModelNotFound(baymodel_id)
-
     def create_baymodel(self, values):
         # ensure defaults are present for new baymodels
         if not values.get('uuid'):
@@ -453,14 +415,6 @@ class Connection(api.Connection):
             except NoResultFound:
                 raise exception.BayModelNotFound(baymodel=baymodel_id)
 
-            # Prevent instance_uuid overwriting
-            if values.get("instance_uuid") and ref.instance_uuid:
-                raise exception.BayModelAssociated(baymodel=baymodel_id,
-                                instance=ref.instance_uuid)
-
-            if 'provision_state' in values:
-                values['provision_updated_at'] = timeutils.utcnow()
-
             ref.update(values)
         return ref
 
diff --git a/magnum/tests/common/test_exception.py b/magnum/tests/common/test_exception.py
index 526ab59b23..5e54a9b3da 100644
--- a/magnum/tests/common/test_exception.py
+++ b/magnum/tests/common/test_exception.py
@@ -143,6 +143,14 @@ class TestException(base.BaseTestCase):
         self.assertRaises(exception.BayNotLocked,
                     lambda: self.raise_(exception.BayNotLocked()))
 
+    def test_BayModelNotFound(self):
+        self.assertRaises(exception.BayModelNotFound,
+                    lambda: self.raise_(exception.BayModelNotFound()))
+
+    def test_BayModelAlreadyExists(self):
+        self.assertRaises(exception.BayModelAlreadyExists,
+                    lambda: self.raise_(exception.BayModelAlreadyExists()))
+
     def test_ContainerNotFound(self):
         self.assertRaises(exception.ContainerNotFound,
                     lambda: self.raise_(exception.ContainerNotFound()))