A method for providing services by a pair of servers to clients through one or more relay agents. The pair includes a second server configured to respond to discovery messages, and a first server configured to be unresponsive to the discovery messages. The method includes: at the first server, receiving a first discovery message from a first relay agent at a first time; and configuring the first server to become responsive to the first discovery message when a number of discovery messages from the first relay agent is equal to or greater than a predetermined number threshold and when a time lapse between the first time and a second time is equal to or greater than a predetermined time threshold. The count and time period are reset if the second server is determined to be responsive to discovery messages by monitoring the client request messages.