diff --git a/swift/common/ring/builder.py b/swift/common/ring/builder.py
index 88932e490d..c3d4d16b6e 100644
--- a/swift/common/ring/builder.py
+++ b/swift/common/ring/builder.py
@@ -367,6 +367,11 @@ class RingBuilder(object):
         # Add holes to self.devs to ensure self.devs[dev['id']] will be the dev
         while dev['id'] >= len(self.devs):
             self.devs.append(None)
+        required_keys = ('ip', 'port', 'weight')
+        if any(required not in dev for required in required_keys):
+            raise ValueError(
+                '%r is missing at least one the required key %r' % (
+                    dev, required_keys))
         dev['weight'] = float(dev['weight'])
         dev['parts'] = 0
         self.devs[dev['id']] = dev
@@ -1657,10 +1662,8 @@ class RingBuilder(object):
             # NOTE(akscram): An old ring builder file don't contain
             #                replication parameters.
             if dev:
-                if 'ip' in dev:
-                    dev.setdefault('replication_ip', dev['ip'])
-                if 'port' in dev:
-                    dev.setdefault('replication_port', dev['port'])
+                dev.setdefault('replication_ip', dev['ip'])
+                dev.setdefault('replication_port', dev['port'])
         return builder
 
     def save(self, builder_file):
diff --git a/test/unit/common/ring/test_builder.py b/test/unit/common/ring/test_builder.py
index 8fdc4c9629..c6d6c22fd1 100644
--- a/test/unit/common/ring/test_builder.py
+++ b/test/unit/common/ring/test_builder.py
@@ -229,6 +229,13 @@ class TestRingBuilder(unittest.TestCase):
                              'ip': '127.0.0.1', 'port': 6200})
         self.assertEqual(rb.devs[1]['id'], 1)
         self.assertEqual(dev_id, 1)
+        # some keys are required
+        self.assertRaises(ValueError, rb.add_dev, {})
+        stub_dev = {'weight': 1, 'ip': '127.0.0.1', 'port': 7000}
+        for key in (stub_dev.keys()):
+            dev = stub_dev.copy()
+            dev.pop(key)
+            self.assertRaises(ValueError, rb.add_dev, dev)
 
     def test_set_dev_weight(self):
         rb = ring.RingBuilder(8, 3, 1)