diff --git a/cinder/wsgi.py b/cinder/wsgi.py
index cee88a06e05..168a1a1f04b 100644
--- a/cinder/wsgi.py
+++ b/cinder/wsgi.py
@@ -59,14 +59,21 @@ socket_opts = [
                     "the server securely"),
 ]
 
+eventlet_opts = [
+    cfg.IntOpt('max_header_line',
+               default=16384,
+               help="Maximum line size of message headers to be accepted. "
+                    "max_header_line may need to be increased when using "
+                    "large tokens (typically those generated by the "
+                    "Keystone v3 API with big service catalogs)."),
+]
+
 CONF = cfg.CONF
 CONF.register_opts(socket_opts)
+CONF.register_opts(eventlet_opts)
 
 LOG = logging.getLogger(__name__)
 
-# Raise the default from 8192 to accommodate large tokens
-eventlet.wsgi.MAX_HEADER_LINE = 16384
-
 
 class Server(object):
     """Server class to manage a WSGI server, serving a WSGI application."""
@@ -85,6 +92,8 @@ class Server(object):
         :returns: None
 
         """
+        # Allow operators to customize http requests max header line size.
+        eventlet.wsgi.MAX_HEADER_LINE = CONF.max_header_line
         self.name = name
         self.app = app
         self._host = host or "0.0.0.0"
diff --git a/etc/cinder/cinder.conf.sample b/etc/cinder/cinder.conf.sample
index 5cd4ce1cf85..56f3ec55d69 100644
--- a/etc/cinder/cinder.conf.sample
+++ b/etc/cinder/cinder.conf.sample
@@ -93,6 +93,12 @@
 # Options defined in cinder.wsgi
 #
 
+# Maximum line size of message headers to be accepted.
+# max_header_line may need to be increased when using large
+# tokens (typically those generated by the Keystone v3 API
+# with big service catalogs). (integer value)
+#max_header_line=16384
+
 # Sets the value of TCP_KEEPIDLE in seconds for each server
 # socket. Not supported on OS X. (integer value)
 #tcp_keepidle=600