diff --git a/neutron/api/v2/attributes.py b/neutron/api/v2/attributes.py
index 04875890b22..8eb2c3a587d 100644
--- a/neutron/api/v2/attributes.py
+++ b/neutron/api/v2/attributes.py
@@ -537,8 +537,8 @@ def convert_to_list(data):
         return [data]
 
 
-HOSTNAME_PATTERN = ("(?=^.{1,254}$)(^(?:(?!\d+\.|-)[a-zA-Z0-9_\-]"
-                    "{1,63}(?<!-)\.?)+(?:[a-zA-Z]{2,})$)")
+HOSTNAME_PATTERN = ("(?=^.{1,254}$)(^(?:(?!\d+.|-)[a-zA-Z0-9_\-]{1,62}"
+                    "[a-zA-Z0-9]\.?)+(?:[a-zA-Z]{2,})$)")
 
 HEX_ELEM = '[0-9A-Fa-f]'
 UUID_PATTERN = '-'.join([HEX_ELEM + '{8}', HEX_ELEM + '{4}',
diff --git a/neutron/tests/unit/test_attributes.py b/neutron/tests/unit/test_attributes.py
index 0282cdc0c22..61ff20d0009 100644
--- a/neutron/tests/unit/test_attributes.py
+++ b/neutron/tests/unit/test_attributes.py
@@ -283,6 +283,7 @@ class TestAttributes(base.BaseTestCase):
                     ['www.hostname.com', 'www.hostname.com'],
                     ['77.hostname.com'],
                     ['1000.0.0.1'],
+                    ['111111111111111111111111111111111111111111111111111111111111'],  # noqa
                     None]
 
         for ns in ns_pools: