diff --git a/nova_zvm/tests/unit/virt/zvm/test_driver.py b/nova_zvm/tests/unit/virt/zvm/test_driver.py
index c2f1fdf..bbaf081 100644
--- a/nova_zvm/tests/unit/virt/zvm/test_driver.py
+++ b/nova_zvm/tests/unit/virt/zvm/test_driver.py
@@ -452,9 +452,9 @@ class TestZVMDriver(test.NoDBTestCase):
     @mock.patch('nova_zvm.virt.zvm.driver.ZVMDriver._instance_power_action')
     def test_power_off(self, ipa):
         self.driver.power_off(self._instance)
-        ipa.assert_called_once_with(self._instance, 'guest_softoff')
+        ipa.assert_called_once_with(self._instance, 'guest_softstop')
         self.driver.power_off(self._instance, 60, 10)
-        ipa.assert_any_call(self._instance, 'guest_softoff',
+        ipa.assert_any_call(self._instance, 'guest_softstop',
                             timeout=60, poll_interval=10)
 
     @mock.patch('nova_zvm.virt.zvm.driver.ZVMDriver._instance_power_action')
diff --git a/nova_zvm/virt/zvm/driver.py b/nova_zvm/virt/zvm/driver.py
index 90fa512..0bd64ee 100644
--- a/nova_zvm/virt/zvm/driver.py
+++ b/nova_zvm/virt/zvm/driver.py
@@ -373,8 +373,9 @@ class ZVMDriver(driver.ComputeDriver):
     def _instance_power_action(self, instance, action, *args, **kwargs):
         inst_name = instance['name']
         if self._instance_exists(inst_name):
-            LOG.info(_("Power action %(action)s to instance %(inst_name)s"),
-                     action=action, inst_name=inst_name, instance=instance)
+            LOG.info(_("Power action %(action)s to instance %(inst_name)s") %
+                     {'action': action, 'inst_name': inst_name},
+                     instance=instance)
             self._reqh.call(action, inst_name)
         else:
             LOG.warning(_('Instance %s does not exist'), inst_name,
@@ -383,11 +384,11 @@ class ZVMDriver(driver.ComputeDriver):
     def power_off(self, instance, timeout=0, retry_interval=0):
         """Power off the specified instance."""
         if timeout >= 0 and retry_interval > 0:
-            self._instance_power_action(instance, 'guest_softoff',
+            self._instance_power_action(instance, 'guest_softstop',
                                         timeout=timeout,
                                         poll_interval=retry_interval)
         else:
-            self._instance_power_action(instance, 'guest_softoff')
+            self._instance_power_action(instance, 'guest_softstop')
 
     def power_on(self, context, instance, network_info,
                  block_device_info=None):