diff --git a/vmware_nsxlib/v3/cluster.py b/vmware_nsxlib/v3/cluster.py
index 595543d1..f72633ee 100644
--- a/vmware_nsxlib/v3/cluster.py
+++ b/vmware_nsxlib/v3/cluster.py
@@ -197,14 +197,15 @@ class NSXRequestsHTTPProvider(AbstractHTTPProvider):
         session.mount('http://', adapter)
         session.mount('https://', adapter)
 
-        self.get_default_headers(session, provider)
+        self.get_default_headers(session, provider,
+                                 config.allow_overwrite_header)
 
         return session
 
     def is_connection_exception(self, exception):
         return isinstance(exception, requests_exceptions.ConnectionError)
 
-    def get_default_headers(self, session, provider):
+    def get_default_headers(self, session, provider, allow_overwrite_header):
         """Get the default headers that should be added to future requests"""
         session.default_headers = {}
 
@@ -236,6 +237,10 @@ class NSXRequestsHTTPProvider(AbstractHTTPProvider):
                      "headers %(hdr)s",
                      {'url': provider.url, 'hdr': session.default_headers})
 
+        # Add allow-overwrite if configured
+        if allow_overwrite_header:
+            session.default_headers['X-Allow-Overwrite'] = 'true'
+
 
 class ClusterHealth(object):
     """Indicator of overall cluster health.
diff --git a/vmware_nsxlib/v3/config.py b/vmware_nsxlib/v3/config.py
index 47a754ec..e1935c81 100644
--- a/vmware_nsxlib/v3/config.py
+++ b/vmware_nsxlib/v3/config.py
@@ -68,7 +68,10 @@ class NsxLibConfig(object):
     :param dns_domain: Domain to use for building the hostnames.
     :param dhcp_profile_uuid: Currently unused and deprecated.
                               Kept for backward compatibility.
-
+    :param allow_overwrite_header: If True, a default header of
+                                   X-Allow-Overwrite:true will be added to all
+                                   the requests, to allow admin user to update/
+                                   delete all entries.
     """
 
     def __init__(self,
@@ -90,7 +93,8 @@ class NsxLibConfig(object):
                  plugin_ver=None,
                  dns_nameservers=None,
                  dns_domain='openstacklocal',
-                 dhcp_profile_uuid=None):
+                 dhcp_profile_uuid=None,
+                 allow_overwrite_header=False):
 
         self.nsx_api_managers = nsx_api_managers
         self._username = username
@@ -110,6 +114,7 @@ class NsxLibConfig(object):
         self.plugin_ver = plugin_ver
         self.dns_nameservers = dns_nameservers or []
         self.dns_domain = dns_domain
+        self.allow_overwrite_header = allow_overwrite_header
 
         if dhcp_profile_uuid:
             # this is deprecated, and never used.