A device management method comprising the steps of: receiving, by a Peripheral Components Interface express, PCIe, switch, diagnostic information sent by a Non-Volatile Memory express, NVMe, subsystem, wherein the diagnostic information is used to indicate at least one of a software version, a hardware version, or a running status of the NVMe subsystem; and sending, by the PCIe switch, the diagnostic information to a device management controller; before the receiving, by the PCIe switch, diagnostic information sent by the NVMe subsystem, further comprising: sending, by the PCIe switch, a first diagnostic information acquiring request to the NVMe subsystem, so that the the NVMe subsystem sends the diagnostic information to the PCIe switch according to the first diagnostic information acquiring request; wherein the sending, by the PCIe switch, a first diagnostic information acquiring request to the NVMe subsystem, so that the NVMe subsystem (13a sends the diagnostic information to the PCIe switch according to the first diagnostic information acquiring request comprises: broadcasting, by the PCIe switch, a first multi-channel transmission platform, MCTP, packet to the NVMe subsystem, wherein the first diagnostic information acquiring request is encapsulated in the first MCTP packet, so that the NVMe subsystem acquires the diagnostic information according to the first diagnostic information acquiring request, and the NVMe subsystem encapsulates the diagnostic information in a second MCTP packet and sends the diagnostic information to the PCIe switch. receiving, by a Peripheral Components Interface express, PCIe, switch, diagnostic information sent by a Non-Volatile Memory express, NVMe, subsystem, wherein the diagnostic information is used to indicate at least one of a software version, a hardware version, or a running status of the NVMe subsystem; and sending, by the PCIe switch, the diagnostic information to a device management controller; before the receiving, by the PCIe switch, diagnostic information sent by the NVMe subsystem, further comprising: sending, by the PCIe switch, a first diagnostic information acquiring request to the NVMe subsystem, so that the the NVMe subsystem sends the diagnostic information to the PCIe switch according to the first diagnostic information acquiring request; wherein the sending, by the PCIe switch, a first diagnostic information acquiring request to the NVMe subsystem, so that the NVMe subsystem (13a sends the diagnostic information to the PCIe switch according to the first diagnostic information acquiring request comprises: broadcasting, by the PCIe switch, a first multi-channel transmission platform, MCTP, packet to the NVMe subsystem, wherein the first diagnostic information acquiring request is encapsulated in the first MCTP packet, so that the NVMe subsystem acquires the diagnostic information according to the first diagnostic information acquiring request, and the NVMe subsystem encapsulates the diagnostic information in a second MCTP packet and sends the diagnostic information to the PCIe switch. sending, by the PCIe switch, a first diagnostic information acquiring request to the NVMe subsystem, so that the the NVMe subsystem sends the diagnostic information to the PCIe switch according to the first diagnostic information acquiring request; wherein the sending, by the PCIe switch, a first diagnostic information acquiring request to the NVMe subsystem, so that the NVMe subsystem (13a sends the diagnostic information to the PCIe switch according to the first diagnostic information acquiring request comprises: broadcasting, by the PCIe switch, a first multi-channel transmission platform, MCTP, packet to the NVMe subsystem, wherein the first diagnostic information acquiring request is encapsulated in the first MCTP packet, so that the NVMe subsystem acquires the diagnostic information according to the first diagnostic information acquiring request, and the NVMe subsystem encapsulates the diagnostic information in a second MCTP packet and sends the diagnostic information to the PCIe switch.