Fix Octavia round robin traffic test error

The Octavia resources require additional time besides having its resources
to reach ACTIVE provisioning status.

This patch adds ShellCommandFailed to the list of exceptions we ignore
for some time after provisioning Octavia resources.

Change-Id: Id5e83c927f2d65386b62ed1caa343a651db7f163

tobiko/openstack/octavia/_validators.py

@@ -69,6 +69,8 @@ def check_members_balanced(ip_address: str,
             if ex.exit_status == 28:
                 raise octavia.TrafficTimeoutError(
                     reason=str(ex.stderr)) from ex
+            else:
+                raise ex
 
         replies[content] += 1
 

tobiko/tests/scenario/octavia/test_traffic.py

@@ -77,6 +77,9 @@ class OctaviaBasicTrafficScenarioTest(testtools.TestCase):
 
     @pytest.mark.flaky(reruns=3)
     def test_round_robin_traffic(self):
+
+        # For 30 seconds we ignore specific exceptions as we know that Octavia
+        # resources are being provisioned
         for attempt in tobiko.retry(timeout=30.):
             try:
                 octavia.check_members_balanced(
@@ -89,7 +92,10 @@ class OctaviaBasicTrafficScenarioTest(testtools.TestCase):
                 break
 
             except (octavia.RoundRobinException,
-                    octavia.TrafficTimeoutError) as e:
+                    octavia.TrafficTimeoutError,
+                    sh.ShellCommandFailed) as e:
+                LOG.debug(f"Traffic couldn't reach for the #{attempt.count} "
+                          f"time, because of the next exception: {e}")
                 if attempt.is_last:
                     raise e