diff --git a/nailgun/nailgun/extensions/cluster_upgrade/tests/test_upgrade.py b/nailgun/nailgun/extensions/cluster_upgrade/tests/test_upgrade.py
index 7e1dee292b..4feeda9db6 100644
--- a/nailgun/nailgun/extensions/cluster_upgrade/tests/test_upgrade.py
+++ b/nailgun/nailgun/extensions/cluster_upgrade/tests/test_upgrade.py
@@ -140,3 +140,43 @@ class TestUpgradeHelperCloneCluster(base_tests.BaseCloneClusterTest):
             self.src_cluster.id)
         self.assertEqual(relation.orig_cluster_id, self.src_cluster.id)
         self.assertEqual(relation.seed_cluster_id, new_cluster.id)
+
+    def _check_dns_and_ntp_list_values(self, new_cluster, dns_list, ntp_list):
+        self.assertEqual(
+            new_cluster.editable_attrs["external_ntp"]["ntp_list"]["value"],
+            ntp_list)
+        self.assertEqual(
+            new_cluster.editable_attrs["external_dns"]["dns_list"]["value"],
+            dns_list)
+        self.assertEqual(
+            new_cluster.editable_attrs["external_ntp"]["ntp_list"]["type"],
+            "text_list")
+        self.assertEqual(
+            new_cluster.editable_attrs["external_dns"]["dns_list"]["type"],
+            "text_list")
+
+    def test_cluster_copy_attrs_with_different_types_dns_and_ntp_lists(self):
+        attrs = copy.deepcopy(self.src_cluster.editable_attrs)
+        attrs["external_ntp"]["ntp_list"]["type"] = "text"
+        attrs["external_ntp"]["ntp_list"]["value"] = "1,2,3"
+        attrs["external_dns"]["dns_list"]["type"] = "text"
+        attrs["external_dns"]["dns_list"]["value"] = "4,5,6"
+        self.src_cluster.editable_attrs = attrs
+        new_cluster = self.helper.create_cluster_clone(
+            self.src_cluster, self.data)
+        self.helper.copy_attributes(self.src_cluster, new_cluster)
+        self._check_dns_and_ntp_list_values(
+            new_cluster, ["4", "5", "6"], ["1", "2", "3"])
+
+    def test_cluster_copy_attrs_with_same_types_dns_and_ntp_lists(self):
+        attrs = copy.deepcopy(self.src_cluster.editable_attrs)
+        attrs["external_ntp"]["ntp_list"]["type"] = "text_list"
+        attrs["external_ntp"]["ntp_list"]["value"] = ["1", "2", "3"]
+        attrs["external_dns"]["dns_list"]["type"] = "text_list"
+        attrs["external_dns"]["dns_list"]["value"] = ["4", "5", "6"]
+        self.src_cluster.editable_attrs = attrs
+        new_cluster = self.helper.create_cluster_clone(
+            self.src_cluster, self.data)
+        self.helper.copy_attributes(self.src_cluster, new_cluster)
+        self._check_dns_and_ntp_list_values(
+            new_cluster, ["4", "5", "6"], ["1", "2", "3"])
diff --git a/nailgun/nailgun/extensions/cluster_upgrade/upgrade.py b/nailgun/nailgun/extensions/cluster_upgrade/upgrade.py
index b84e366e1a..7cd771e8ad 100644
--- a/nailgun/nailgun/extensions/cluster_upgrade/upgrade.py
+++ b/nailgun/nailgun/extensions/cluster_upgrade/upgrade.py
@@ -41,6 +41,13 @@ def merge_attributes(a, b):
         for key, values in six.iteritems(pairs):
             if key != "metadata" and key in a_values:
                 values["value"] = a_values[key]["value"]
+                # NOTE: In the mitaka-9.0 release types of values dns_list and
+                # ntp_list were changed from 'text'
+                # (a string of comma-separated IP-addresses)
+                # to 'text_list' (a list of strings of IP-addresses).
+                if a_values[key]['type'] == 'text' and \
+                        values['type'] == 'text_list':
+                    values["value"] = values['value'].split(',')
     return attrs