diff --git a/heat/engine/service_software_config.py b/heat/engine/service_software_config.py
index c90f14f58a..6d036d1b43 100644
--- a/heat/engine/service_software_config.py
+++ b/heat/engine/service_software_config.py
@@ -108,22 +108,37 @@ class SoftwareConfigService(object):
         deployments = self.metadata_software_deployments(cnxt, server_id)
         md = rs.rsrc_metadata or {}
         md['deployments'] = deployments
-        rows_updated = db_api.resource_update(
-            cnxt, rs.id, {'rsrc_metadata': md}, rs.atomic_key)
-        if not rows_updated:
-            action = _('deployments of server %s') % server_id
-            raise exception.ConcurrentTransaction(action=action)
 
         metadata_put_url = None
         metadata_queue_id = None
+        metadata_headers = None
         for rd in rs.data:
             if rd.key == 'metadata_put_url':
                 metadata_put_url = rd.value
             if rd.key == 'metadata_queue_id':
                 metadata_queue_id = rd.value
+        if metadata_put_url:
+            data = requests.head(metadata_put_url)
+            etag = data.headers.get('etag')
+            if etag:
+                metadata_headers = {'if-match': etag}
+            else:
+                LOG.warning('Couldn\'t find existing Swift metadata')
+
+        rows_updated = db_api.resource_update(
+            cnxt, rs.id, {'rsrc_metadata': md}, rs.atomic_key)
+        if not rows_updated:
+            LOG.debug('Conflict on database deployment update, retrying')
+            action = _('deployments of server %s') % server_id
+            raise exception.ConcurrentTransaction(action=action)
         if metadata_put_url:
             json_md = jsonutils.dumps(md)
-            requests.put(metadata_put_url, json_md)
+            resp = requests.put(metadata_put_url, json_md,
+                                headers=metadata_headers)
+            if resp.status_code == 412:
+                LOG.debug('Conflict on Swift deployment update, retrying')
+                action = _('deployments of server %s') % server_id
+                raise exception.ConcurrentTransaction(action=action)
         if metadata_queue_id:
             project = stack_user_project_id
             queue = self._get_zaqar_queue(cnxt, rs, project, metadata_queue_id)
diff --git a/heat/tests/engine/service/test_software_config.py b/heat/tests/engine/service/test_software_config.py
index c99d15565e..38c23eeb78 100644
--- a/heat/tests/engine/service/test_software_config.py
+++ b/heat/tests/engine/service/test_software_config.py
@@ -692,8 +692,9 @@ class SoftwareConfigServiceTest(common.HeatTestCase):
     @mock.patch.object(db_api, 'resource_update')
     @mock.patch.object(db_api, 'resource_get_by_physical_resource_id')
     @mock.patch.object(service_software_config.requests, 'put')
+    @mock.patch.object(service_software_config.requests, 'head')
     def test_push_metadata_software_deployments_temp_url(
-            self, put, res_get, res_upd, md_sd):
+            self, head, put, res_get, res_upd, md_sd):
         rs = mock.Mock()
         rs.rsrc_metadata = {'original': 'metadata'}
         rs.id = '1234'
@@ -705,6 +706,14 @@ class SoftwareConfigServiceTest(common.HeatTestCase):
         res_get.return_value = rs
         res_upd.return_value = 1
 
+        head_response = mock.Mock()
+        head_response.headers = {'etag': '1234'}
+        head_response.status_code = 200
+        head.return_value = head_response
+
+        put_response = mock.Mock()
+        put_response.status_code = 201
+
         deployments = {'deploy': 'this'}
         md_sd.return_value = deployments
 
@@ -719,7 +728,8 @@ class SoftwareConfigServiceTest(common.HeatTestCase):
             self.ctx, '1234', {'rsrc_metadata': result_metadata}, 1)
 
         put.assert_called_once_with(
-            'http://192.168.2.2/foo/bar', json.dumps(result_metadata))
+            'http://192.168.2.2/foo/bar', json.dumps(result_metadata),
+            headers={'if-match': '1234'})
 
     @mock.patch.object(service_software_config.SoftwareConfigService,
                        'metadata_software_deployments')