diff --git a/app/models/incoming_domain.rb b/app/models/incoming_domain.rb
index fac5b620033..857b39b3e08 100644
--- a/app/models/incoming_domain.rb
+++ b/app/models/incoming_domain.rb
@@ -11,7 +11,7 @@ class IncomingDomain < ActiveRecord::Base
 
     begin
       current = create!(name: name, https: https, port: port)
-    rescue
+    rescue ActiveRecord::RecordNotUnique
       # duplicate key is just ignored
     end
 
diff --git a/app/models/incoming_referer.rb b/app/models/incoming_referer.rb
index 450e54f8cb2..343ac5cf655 100644
--- a/app/models/incoming_referer.rb
+++ b/app/models/incoming_referer.rb
@@ -11,8 +11,8 @@ class IncomingReferer < ActiveRecord::Base
 
     begin
       current = create!(path: path, incoming_domain_id: domain_id)
-    rescue
-      # duplicates
+    rescue ActiveRecord::RecordNotUnique
+      # does not matter
     end
 
     current || find_by(path: path, incoming_domain_id: domain_id)