A node controller-based request responding method, wherein the method comprises: receiving, by a first node controller, a first packet, wherein the first packet is a snoop packet from an interface of a CPU or a snoop request packet from an interface of another node controller; acquiring an information directory, and querying, in the information directory, whether a memory address requested by the first packet is occupied by a second node controller, wherein the information directory comprises information about a memory address of a current node controller being occupied by another node controller; characterised in that when the memory address requested by the first packet is occupied by the second node controller, querying node presence information to determine whether the second node controller exists; and generating and sending an invalid response packet when it is determined that the second node controller does not exist, wherein a destination node identifier DNID of the invalid response packet is a source node identifier SNID of the first packet, and an SNID of the invalid response packet is a DNID of the first packet, wherein after the generating and sending an invalid response packet when it is determined that the second node controller does not exist, the method further comprises: modifying, in the information directory, information about a memory address of the first node controller being occupied by the second node controller, releasing the memory address occupied by the second node controller, and updating the node presence information to update information about the second node controller to that the second node controller does not exist. receiving, by a first node controller, a first packet, wherein the first packet is a snoop packet from an interface of a CPU or a snoop request packet from an interface of another node controller; acquiring an information directory, and querying, in the information directory, whether a memory address requested by the first packet is occupied by a second node controller, wherein the information directory comprises information about a memory address of a current node controller being occupied by another node controller; characterised in that when the memory address requested by the first packet is occupied by the second node controller, querying node presence information to determine whether the second node controller exists; and generating and sending an invalid response packet when it is determined that the second node controller does not exist, wherein a destination node identifier DNID of the invalid response packet is a source node identifier SNID of the first packet, and an SNID of the invalid response packet is a DNID of the first packet, wherein after the generating and sending an invalid response packet when it is determined that the second node controller does not exist, the method further comprises: modifying, in the information directory, information about a memory address of the first node controller being occupied by the second node controller, releasing the memory address occupied by the second node controller, and updating the node presence information to update information about the second node controller to that the second node controller does not exist. modifying, in the information directory, information about a memory address of the first node controller being occupied by the second node controller, releasing the memory address occupied by the second node controller, and updating the node presence information to update information about the second node controller to that the second node controller does not exist.