Fixing neutron-metering-agent for icehouse

neutron_services_metering_drivers_iptables_iptables_driver.py.patch

diff --git a/neutron/services/metering/drivers/iptables/iptables_driver.py b/neutron/services/metering/drivers/iptables/iptables_driver.py
index 6c32905..d0faf52 100644
--- a/neutron/services/metering/drivers/iptables/iptables_driver.py
+++ b/neutron/services/metering/drivers/iptables/iptables_driver.py
@@ -268,20 +268,26 @@ class IptablesMeteringDriver(abstract_driver.MeteringAbstractDriver):
                 continue
 
             for label_id, label in rm.metering_labels.items():
-                chain = iptables_manager.get_chain_name(WRAP_NAME + LABEL +
-                                                        label_id, wrap=False)
+                try:
+                    chain = iptables_manager.get_chain_name(WRAP_NAME + LABEL +
+                                                            label_id, wrap=False)
 
-                chain_acc = rm.iptables_manager.get_traffic_counters(
-                    chain, wrap=False, zero=True)
+                    chain_acc = rm.iptables_manager.get_traffic_counters(
+                        chain, wrap=False, zero=True)
 
-                if not chain_acc:
-                    continue
+                    if not chain_acc:
+                        continue
+
+                    acc = accs.get(label_id, {'pkts': 0, 'bytes': 0})
 
-                acc = accs.get(label_id, {'pkts': 0, 'bytes': 0})
+                    acc['pkts'] += chain_acc['pkts']
+                    acc['bytes'] += chain_acc['bytes']
 
-                acc['pkts'] += chain_acc['pkts']
-                acc['bytes'] += chain_acc['bytes']
+                    accs[label_id] = acc
+                except RuntimeError:
+                    LOG.exception(_("Driver %(driver)s:%(func)s runtime error"),
+                                {'driver': self.conf.driver,
+                                'func': 'get_traffic_counters'})
 
-                accs[label_id] = acc
 
         return accs