A peripheral component interconnect express, PCIE, switch-based server system, comprising: an active PCIE switch device, wherein the active PCIE switch device comprises a communication interface and a first PCIE switch module, and the first PCIE switch module comprises at least two first PCIE ports; a standby PCIE switch device, wherein the standby PCIE switch device comprises a communication interface and a first PCIE switch module, and the first PCIE switch module comprises at least two first PCIE ports; and a host, wherein the host comprises two third PCIE ports, one third PCIE port is connected to the other first PCIE port of the at least two first PCIE ports of the active PCIE switch device, and the other third PCIE port is connected to the other first PCIE port of the at least two first PCIE ports of the standby PCIE switch device, wherein the communication interface of the active PCIE switch device and the communication interface of the standby PCIE switch device are interconnected, so that the standby PCIE switch device obtains switch network configuration information of the active PCIE switch device through the communication interface of the active PCIE switch device and the communication interface of the standby PCIE switch device; the host further comprises a third control module, the third control module comprises a third central processing unit, and the third central processing unit is configured to, after the active-standby switching of the active PCIE switch device and the standby PCIE switch device, open the third PCIE port connected to the active PCIE switch device after the switching, adopt port configuration information of the third PCIE port connected to the active PCIE switch device before the switching to configure the third PCIE port connected to the active PCIE switch device after the switching, and at the same time, disable the third PCIE port connected to the standby PCIE switch device after the switching. an active PCIE switch device, wherein the active PCIE switch device comprises a communication interface and a first PCIE switch module, and the first PCIE switch module comprises at least two first PCIE ports; a standby PCIE switch device, wherein the standby PCIE switch device comprises a communication interface and a first PCIE switch module, and the first PCIE switch module comprises at least two first PCIE ports; and a host, wherein the host comprises two third PCIE ports, one third PCIE port is connected to the other first PCIE port of the at least two first PCIE ports of the active PCIE switch device, and the other third PCIE port is connected to the other first PCIE port of the at least two first PCIE ports of the standby PCIE switch device, wherein the communication interface of the active PCIE switch device and the communication interface of the standby PCIE switch device are interconnected, so that the standby PCIE switch device obtains switch network configuration information of the active PCIE switch device through the communication interface of the active PCIE switch device and the communication interface of the standby PCIE switch device; the host further comprises a third control module, the third control module comprises a third central processing unit, and the third central processing unit is configured to, after the active-standby switching of the active PCIE switch device and the standby PCIE switch device, open the third PCIE port connected to the active PCIE switch device after the switching, adopt port configuration information of the third PCIE port connected to the active PCIE switch device before the switching to configure the third PCIE port connected to the active PCIE switch device after the switching, and at the same time, disable the third PCIE port connected to the standby PCIE switch device after the switching.