diff --git a/neutron/db/l3_hamode_db.py b/neutron/db/l3_hamode_db.py
index 8553d00c598..96647d8b1c9 100644
--- a/neutron/db/l3_hamode_db.py
+++ b/neutron/db/l3_hamode_db.py
@@ -262,13 +262,13 @@ class L3_HA_NAT_db_mixin(l3_dvr_db.L3_NAT_with_dvr_db_mixin):
         """
 
         min_agents = cfg.CONF.min_l3_agents_per_router
-        num_agents = len(self.get_l3_agents(context,
+        num_agents = len(self.get_l3_agents(context, active=True,
             filters={'agent_modes': [constants.L3_AGENT_MODE_LEGACY,
                                      constants.L3_AGENT_MODE_DVR_SNAT]}))
         max_agents = cfg.CONF.max_l3_agents_per_router
         if max_agents:
             if max_agents > num_agents:
-                LOG.info(_LI("Number of available agents lower than "
+                LOG.info(_LI("Number of active agents lower than "
                              "max_l3_agents_per_router. L3 agents "
                              "available: %s"), num_agents)
             else:
diff --git a/neutron/tests/unit/db/test_l3_hamode_db.py b/neutron/tests/unit/db/test_l3_hamode_db.py
index e13991aa0e0..bd8f9e9cd44 100644
--- a/neutron/tests/unit/db/test_l3_hamode_db.py
+++ b/neutron/tests/unit/db/test_l3_hamode_db.py
@@ -12,8 +12,10 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+import datetime
 import mock
 from oslo_config import cfg
+from oslo_utils import timeutils
 
 from neutron.api.v2 import attributes
 from neutron.common import constants
@@ -52,22 +54,28 @@ class L3HATestFramework(testlib_api.SqlTestCase):
         cfg.CONF.set_override('allow_overlapping_ips', True)
 
         self.plugin = FakeL3PluginWithAgents()
-        self._register_agents()
+        self.agent1 = self._register_agent('legacy', 'l3host')
+        self.agent2 = self._register_agent('dvr_snat', 'l3host_2')
 
-    def _register_agents(self):
+    def _register_agent(self, agent_mode, host):
         agent_status = {
             'agent_type': constants.AGENT_TYPE_L3,
             'binary': 'neutron-l3-agent',
-            'host': 'l3host',
+            'host': host,
             'topic': 'N/A',
-            'configurations': {'agent_mode': 'legacy'}
+            'configurations': {'agent_mode': agent_mode}
         }
 
         self.plugin.create_or_update_agent(self.admin_ctx, agent_status)
-        agent_status['host'] = 'l3host_2'
-        agent_status['configurations'] = {'agent_mode': 'dvr_snat'}
-        self.plugin.create_or_update_agent(self.admin_ctx, agent_status)
-        self.agent1, self.agent2 = self.plugin.get_agents(self.admin_ctx)
+        return self.plugin.get_agents(
+            self.admin_ctx, filters={'host': [host]})[0]
+
+    def _bring_down_agent(self, agent_id):
+        update = {
+            'agent': {
+                'heartbeat_timestamp':
+                timeutils.utcnow() - datetime.timedelta(hours=1)}}
+        self.plugin.update_agent(self.admin_ctx, agent_id, update)
 
     def _create_router(self, ha=True, tenant_id='tenant1', distributed=None,
                        ctx=None):
@@ -478,6 +486,14 @@ class L3HATestCase(L3HATestFramework):
             self.admin_ctx)
         self.assertEqual(2, num_ha_candidates)
 
+    def test_get_number_of_agents_for_scheduling_not_enough_agents(self):
+        cfg.CONF.set_override('min_l3_agents_per_router', 3)
+        agent_to_bring_down = self._register_agent('legacy', 'l3host_3')
+        self._bring_down_agent(agent_to_bring_down['id'])
+        self.assertRaises(l3_ext_ha_mode.HANotEnoughAvailableAgents,
+                          self.plugin.get_number_of_agents_for_scheduling,
+                          self.admin_ctx)
+
 
 class L3HAModeDbTestCase(L3HATestFramework):
 
diff --git a/neutron/tests/unit/scheduler/test_l3_agent_scheduler.py b/neutron/tests/unit/scheduler/test_l3_agent_scheduler.py
index 09e3f708021..f7ee3d766fe 100644
--- a/neutron/tests/unit/scheduler/test_l3_agent_scheduler.py
+++ b/neutron/tests/unit/scheduler/test_l3_agent_scheduler.py
@@ -1641,10 +1641,10 @@ class L3HAChanceSchedulerTestCase(L3HATestCaseMixin):
             admin_state_up=True)
         self.assertEqual(2, len(agents))
 
+        r2 = self._create_ha_router()
         self._set_l3_agent_admin_state(self.adminContext,
                                        self.agent_id2, False)
 
-        r2 = self._create_ha_router()
         self.plugin.schedule_router(self.adminContext, r2['id'])
         agents = self.plugin.get_l3_agents_hosting_routers(
             self.adminContext, [r2['id']],