A redirector, a relay, a system for configuring route information, and a method for updating route information are disclosed herein. The redirector includes: a route storing module and a route indicating module. The redirector further includes: a monitoring module which is coupled to communicate with the route storing module and configured to monitor change of the route configuration information; and a notifying module which is coupled to communicate with the monitoring module and configured to send a notification to the intermediate node managed by the redirector, where the notification indicates that the route information corresponding to the changed route configuration information is invalid. Through the foregoing solution, after the route configuration information changes, a notification may be sent in time to indicate that the previously subscribed route indication information is invalid, thus better ensuring correct forwarding of the service request message and improving the QoS.