Fix 'ntpd -gq' false-positive exit code 0

Command 'ntpd -gq' is finished with exit code 0 even if
"no servers found" appeared.

Change-Id: Ib45afe7fccca91b402c8f370ede8f963e550921f
Related-Bug: #1656020

devops/helpers/ntp.py

@@ -94,13 +94,25 @@ class BaseNtp(AbstractNtp):
     - set_actual_time
     - wait_peer
     """
+    set_date_cmd = "ntpd -gqd"
+
+    def _set_time(self):
+        # Try to get current time from a parent server
+        res = self.remote.execute(self.set_date_cmd)
+
+        if res['exit_code']:
+            # Exit code is not 0
+            return False
+        if any(['no servers found' in s for s in res['stdout']]):
+            # Workaround for "exit_code == 0" if no servers found
+            return False
+
+        return True
 
     def set_actual_time(self, timeout=600):
-
-        # Waiting for parent server until it starts providing the time
-        set_date_cmd = "ntpd -gq"
+        # Wait for a parent server until it starts providing the time
         helpers.wait(
-            lambda: not self.remote.execute(set_date_cmd)['exit_code'],
+            self._set_time,
             timeout=timeout,
             timeout_msg='Failed to set actual time on node {!r}'.format(
                 self._node_name))

devops/tests/helpers/test_ntp.py

@@ -134,7 +134,7 @@ class TestNtpInitscript(NtpTestCase):
         self.remote_mock.execute.assert_has_calls((
             mock.call(
                 "find /etc/init.d/ -regex '/etc/init.d/ntp.?' -executable"),
-            mock.call('ntpd -gq'),
+            mock.call('ntpd -gqd'),
         ))
 
         self.remote_mock.check_call.assert_called_once_with('hwclock -w')