diff --git a/neutron/agent/l3_agent.py b/neutron/agent/l3_agent.py
index ebef90774bc..b31c7465bef 100644
--- a/neutron/agent/l3_agent.py
+++ b/neutron/agent/l3_agent.py
@@ -243,14 +243,18 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback, manager.Manager):
 
         If only_router_id is passed, only destroy single namespace, to allow
         for multiple l3 agents on the same host, without stepping on each
-        other's toes on init.  This only makes sense if router_id is set.
+        other's toes on init.  This only makes sense if only_router_id is set.
         """
         root_ip = ip_lib.IPWrapper(self.root_helper)
         for ns in root_ip.get_namespaces(self.root_helper):
             if ns.startswith(NS_PREFIX):
-                if only_router_id and not ns.endswith(only_router_id):
+                router_id = ns[len(NS_PREFIX):]
+                if only_router_id and not only_router_id == router_id:
                     continue
 
+                if self.conf.enable_metadata_proxy:
+                    self._destroy_metadata_proxy(router_id, ns)
+
                 try:
                     self._destroy_router_namespace(ns)
                 except Exception:
@@ -304,7 +308,7 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback, manager.Manager):
         ri.iptables_manager.apply()
         super(L3NATAgent, self).process_router_add(ri)
         if self.conf.enable_metadata_proxy:
-            self._spawn_metadata_proxy(ri)
+            self._spawn_metadata_proxy(ri.router_id, ri.ns_name())
 
     def _router_removed(self, router_id):
         ri = self.router_info.get(router_id)
@@ -322,37 +326,37 @@ class L3NATAgent(firewall_l3_agent.FWaaSL3AgentRpcCallback, manager.Manager):
             ri.iptables_manager.ipv4['nat'].remove_rule(c, r)
         ri.iptables_manager.apply()
         if self.conf.enable_metadata_proxy:
-            self._destroy_metadata_proxy(ri)
+            self._destroy_metadata_proxy(ri.router_id, ri.ns_name())
         del self.router_info[router_id]
         self._destroy_router_namespace(ri.ns_name())
 
-    def _spawn_metadata_proxy(self, router_info):
+    def _spawn_metadata_proxy(self, router_id, ns_name):
         def callback(pid_file):
             metadata_proxy_socket = cfg.CONF.metadata_proxy_socket
             proxy_cmd = ['neutron-ns-metadata-proxy',
                          '--pid_file=%s' % pid_file,
                          '--metadata_proxy_socket=%s' % metadata_proxy_socket,
-                         '--router_id=%s' % router_info.router_id,
+                         '--router_id=%s' % router_id,
                          '--state_path=%s' % self.conf.state_path,
                          '--metadata_port=%s' % self.conf.metadata_port]
             proxy_cmd.extend(config.get_log_args(
                 cfg.CONF, 'neutron-ns-metadata-proxy-%s.log' %
-                router_info.router_id))
+                router_id))
             return proxy_cmd
 
         pm = external_process.ProcessManager(
             self.conf,
-            router_info.router_id,
+            router_id,
             self.root_helper,
-            router_info.ns_name())
+            ns_name)
         pm.enable(callback)
 
-    def _destroy_metadata_proxy(self, router_info):
+    def _destroy_metadata_proxy(self, router_id, ns_name):
         pm = external_process.ProcessManager(
             self.conf,
-            router_info.router_id,
+            router_id,
             self.root_helper,
-            router_info.ns_name())
+            ns_name)
         pm.disable()
 
     def _set_subnet_info(self, port):
diff --git a/neutron/services/firewall/agents/varmour/varmour_router.py b/neutron/services/firewall/agents/varmour/varmour_router.py
index d7f3efe2e82..b359ae18024 100755
--- a/neutron/services/firewall/agents/varmour/varmour_router.py
+++ b/neutron/services/firewall/agents/varmour/varmour_router.py
@@ -88,10 +88,10 @@ class vArmourL3NATAgent(l3_agent.L3NATAgent,
 
             del self.router_info[router_id]
 
-    def _spawn_metadata_proxy(self, router_info):
+    def _spawn_metadata_proxy(self, router_id, ns_name):
         return
 
-    def _destroy_metadata_proxy(self, router_info):
+    def _destroy_metadata_proxy(self, router_id, ns_name):
         return
 
     def _set_subnet_info(self, port):
diff --git a/neutron/tests/unit/test_l3_agent.py b/neutron/tests/unit/test_l3_agent.py
index eb93047f374..becb04a7b4e 100644
--- a/neutron/tests/unit/test_l3_agent.py
+++ b/neutron/tests/unit/test_l3_agent.py
@@ -668,12 +668,12 @@ class TestBasicRouterOperations(base.BaseTestCase):
                 agent, '_spawn_metadata_proxy') as spawn_proxy:
                 agent._router_added(router_id, router)
                 if enableflag:
-                    spawn_proxy.assert_called_with(mock.ANY)
+                    spawn_proxy.assert_called_with(mock.ANY, mock.ANY)
                 else:
                     self.assertFalse(spawn_proxy.call_count)
                 agent._router_removed(router_id)
                 if enableflag:
-                    destroy_proxy.assert_called_with(mock.ANY)
+                    destroy_proxy.assert_called_with(mock.ANY, mock.ANY)
                 else:
                     self.assertFalse(destroy_proxy.call_count)
 
@@ -783,19 +783,13 @@ class TestL3AgentEventHandler(base.BaseTestCase):
         cfg.CONF.set_override('log_file', 'test.log')
         cfg.CONF.set_override('debug', True)
 
-        router_info = l3_agent.RouterInfo(
-            router_id, cfg.CONF.root_helper, cfg.CONF.use_namespaces, None
-        )
-
         self.external_process_p.stop()
+        ns = 'qrouter-' + router_id
         try:
             with mock.patch(ip_class_path) as ip_mock:
-                self.agent._spawn_metadata_proxy(router_info)
+                self.agent._spawn_metadata_proxy(router_id, ns)
                 ip_mock.assert_has_calls([
-                    mock.call(
-                        'sudo',
-                        'qrouter-' + router_id
-                    ),
+                    mock.call('sudo', ns),
                     mock.call().netns.execute([
                         'neutron-ns-metadata-proxy',
                         mock.ANY,