diff --git a/neutron/agent/linux/interface.py b/neutron/agent/linux/interface.py
index 4eea826082c..311e7f5e9c9 100644
--- a/neutron/agent/linux/interface.py
+++ b/neutron/agent/linux/interface.py
@@ -355,7 +355,7 @@ def _add_device_to_namespace(self, ip_wrapper, device, namespace):
         namespace_obj = ip_wrapper.ensure_namespace(namespace)
         for i in range(9):
             try:
-                namespace_obj.add_device_to_namespace(device, is_ovs_port=True)
+                namespace_obj.add_device_to_namespace(device)
                 break
             except ip_lib.NetworkInterfaceNotFound:
                 # NOTE(slaweq): if the exception was NetworkInterfaceNotFound
diff --git a/neutron/agent/linux/ip_lib.py b/neutron/agent/linux/ip_lib.py
index 29f64a3c452..4f88e887297 100644
--- a/neutron/agent/linux/ip_lib.py
+++ b/neutron/agent/linux/ip_lib.py
@@ -270,9 +270,9 @@ def garbage_collect_namespace(self):
                 return True
         return False
 
-    def add_device_to_namespace(self, device, is_ovs_port=False):
+    def add_device_to_namespace(self, device):
         if self.namespace:
-            device.link.set_netns(self.namespace, is_ovs_port=is_ovs_port)
+            device.link.set_netns(self.namespace)
 
     def add_vlan(self, name, physical_interface, vlan_id):
         privileged.create_interface(name,
@@ -462,15 +462,10 @@ def set_down(self):
         privileged.set_link_attribute(
             self.name, self._parent.namespace, state='down')
 
-    def set_netns(self, namespace, is_ovs_port=False):
+    def set_netns(self, namespace):
         privileged.set_link_attribute(
             self.name, self._parent.namespace, net_ns_fd=namespace)
         self._parent.namespace = namespace
-        if is_ovs_port:
-            # NOTE(slaweq): because of the "shy port" which may dissapear for
-            # short time after it's moved to the namespace we need to wait
-            # a bit before checking if port really exists in the namespace
-            time.sleep(1)
         common_utils.wait_until_true(lambda: self.exists, timeout=5,
                                      sleep=0.5)
 
diff --git a/neutron/conf/agent/database/agents_db.py b/neutron/conf/agent/database/agents_db.py
index aad0582bf5a..90569e104d2 100644
--- a/neutron/conf/agent/database/agents_db.py
+++ b/neutron/conf/agent/database/agents_db.py
@@ -16,7 +16,12 @@
 from neutron.common import _constants
 
 AGENT_OPTS = [
+    # The agent_down_time value can only be a max of INT_MAX (as defined in C),
+    # where int is usually 32 bits. The agent_down_time will be passed to
+    # eventlet in milliseconds and any number higher will produce an OverFlow
+    # error. More details here: https://bugs.launchpad.net/neutron/+bug/2028724
     cfg.IntOpt('agent_down_time', default=75,
+               max=((2**32 / 2 - 1) // 1000),
                help=_("Seconds to regard the agent is down; should be at "
                       "least twice report_interval, to be sure the "
                       "agent is down for good.")),
diff --git a/neutron/tests/unit/agent/linux/test_interface.py b/neutron/tests/unit/agent/linux/test_interface.py
index 314a8f89da7..9b3b5ca13eb 100644
--- a/neutron/tests/unit/agent/linux/test_interface.py
+++ b/neutron/tests/unit/agent/linux/test_interface.py
@@ -467,11 +467,11 @@ def device_exists(dev, namespace=None):
                 expected.extend(
                     [mock.call().ensure_namespace(namespace),
                      mock.call().ensure_namespace().add_device_to_namespace(
-                         mock.ANY, is_ovs_port=True),
+                         mock.ANY),
                      mock.call().ensure_namespace().add_device_to_namespace(
-                         mock.ANY, is_ovs_port=True),
+                         mock.ANY),
                      mock.call().ensure_namespace().add_device_to_namespace(
-                         mock.ANY, is_ovs_port=True)])
+                         mock.ANY)])
             expected.extend([
                 mock.call(namespace=namespace),
                 mock.call().device('tap0'),
diff --git a/neutron/tests/unit/agent/linux/test_ip_lib.py b/neutron/tests/unit/agent/linux/test_ip_lib.py
index aeda0fe58f5..72ec748a65a 100644
--- a/neutron/tests/unit/agent/linux/test_ip_lib.py
+++ b/neutron/tests/unit/agent/linux/test_ip_lib.py
@@ -507,8 +507,7 @@ def fake_create_interface(ifname, namespace, kind, **kwargs):
     def test_add_device_to_namespace(self):
         dev = mock.Mock()
         ip_lib.IPWrapper(namespace='ns').add_device_to_namespace(dev)
-        dev.assert_has_calls(
-            [mock.call.link.set_netns('ns', is_ovs_port=False)])
+        dev.assert_has_calls([mock.call.link.set_netns('ns')])
 
     def test_add_device_to_namespace_is_none(self):
         dev = mock.Mock()
diff --git a/releasenotes/notes/agent_down_time_max-af3b62763aaa2fe5.yaml b/releasenotes/notes/agent_down_time_max-af3b62763aaa2fe5.yaml
new file mode 100644
index 00000000000..ec221e2e05a
--- /dev/null
+++ b/releasenotes/notes/agent_down_time_max-af3b62763aaa2fe5.yaml
@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    The config option ``agent_down_time`` is now limited to a maximum value of
+    `2147483`, as neutron-server will fail to start if it is configured higher.
+    See bug `2028724 <https://bugs.launchpad.net/neutron/+bug/2028724>`_ for more information.