An information management method, comprising: generating, by a controller, a first message; and sending, by the controller, the first message to a network device; wherein either: the first message carries an address of a first next hop of the network device, the first message comprises first identification information, and the first identification information is used to instruct the network device to delete, from a next hop table stored in the network device, an entry of the first next hop corresponding to the address of the first next hop, and wherein the entry of the first next hop in the next hop table is associated with one or more routing entries in a routing table of the network device that use the address of the first next hop; and sending the first message to the network device enables the network device to delete the entry of the first next hop as indicated by the first identification information, so that all routing entries associated with the entry of the first next hop in the routing table of the network device become withdrawn; or: the first message carries entry information of the first next hop of the network device, the entry information of the first next hop comprises a mapping relationship between the address of the first next hop and attribute information of the first next hop, the first message comprises first identification information, and the first identification information is used to instruct the network device to store the entry information of the first next hop in the next hop table of the network device, and wherein the entry information of the first next hop in the next hop table is associated with a plurality of routing entries in the routing table of the network device that use the address of the first next hop; and sending the first message to the network device enables the network device to store the entry information of the first next hop into the next hop table based on the first identification information. generating, by a controller, a first message; and sending, by the controller, the first message to a network device; wherein either: the first message carries an address of a first next hop of the network device, the first message comprises first identification information, and the first identification information is used to instruct the network device to delete, from a next hop table stored in the network device, an entry of the first next hop corresponding to the address of the first next hop, and wherein the entry of the first next hop in the next hop table is associated with one or more routing entries in a routing table of the network device that use the address of the first next hop; and sending the first message to the network device enables the network device to delete the entry of the first next hop as indicated by the first identification information, so that all routing entries associated with the entry of the first next hop in the routing table of the network device become withdrawn; or: the first message carries entry information of the first next hop of the network device, the entry information of the first next hop comprises a mapping relationship between the address of the first next hop and attribute information of the first next hop, the first message comprises first identification information, and the first identification information is used to instruct the network device to store the entry information of the first next hop in the next hop table of the network device, and wherein the entry information of the first next hop in the next hop table is associated with a plurality of routing entries in the routing table of the network device that use the address of the first next hop; and sending the first message to the network device enables the network device to store the entry information of the first next hop into the next hop table based on the first identification information. the first message carries an address of a first next hop of the network device, the first message comprises first identification information, and the first identification information is used to instruct the network device to delete, from a next hop table stored in the network device, an entry of the first next hop corresponding to the address of the first next hop, and wherein the entry of the first next hop in the next hop table is associated with one or more routing entries in a routing table of the network device that use the address of the first next hop; and sending the first message to the network device enables the network device to delete the entry of the first next hop as indicated by the first identification information, so that all routing entries associated with the entry of the first next hop in the routing table of the network device become withdrawn; or: the first message carries entry information of the first next hop of the network device, the entry information of the first next hop comprises a mapping relationship between the address of the first next hop and attribute information of the first next hop, the first message comprises first identification information, and the first identification information is used to instruct the network device to store the entry information of the first next hop in the next hop table of the network device, and wherein the entry information of the first next hop in the next hop table is associated with a plurality of routing entries in the routing table of the network device that use the address of the first next hop; and sending the first message to the network device enables the network device to store the entry information of the first next hop into the next hop table based on the first identification information.