diff --git a/quantum/api/v2/base.py b/quantum/api/v2/base.py
index 02b2e935b12..37fedf475b3 100644
--- a/quantum/api/v2/base.py
+++ b/quantum/api/v2/base.py
@@ -47,6 +47,7 @@
              netaddr.AddrFormatError: webob.exc.HTTPBadRequest,
              AttributeError: webob.exc.HTTPBadRequest,
              ValueError: webob.exc.HTTPBadRequest,
+             exceptions.IpAddressGenerationFailure: webob.exc.HTTPConflict,
              }
 
 QUOTAS = quota.QUOTAS