The mode of unidirectional shutdown and bidirectional startup. It indicates the port shutdown mode when a link becomes unidirectional and port startup mode when the link becomes bidirectional. In auto mode, DLDP shuts down a port when detecting a unidirectional link and brings up the port when the link becomes bidirectional. In manual mode, a port requires manual shutdown when DLDP detects a unidirectional link and the port requires manual startup when the link becomes bidirectional.In hybrid mode, DLDP shuts down a port when detecting a unidirectional link and the port requires manual startup when the link becomes bidirectional.