Firmware mirror image switching method and device in computer system and medium

The invention discloses a firmware mirror image switching method and device in a computer system and a computer readable storage medium. The method comprises the steps: recording and storing the normal starting duration of firmware in advance; when the programmable logic device controls the server to be powered on to start firmware, starting timing; when the current accumulated duration reaches the normal starting duration of the firmware, judging whether the firmware is started or not, and if the firmware is not started, switching the firmware from the main firmware to the corresponding backup firmware. According to the method, the normal starting duration corresponding to the firmware is stored in advance, timing is started when the server is controlled to be powered on and started through the programmable logic device, whether the firmware is normally started or not is detected in the timing process, and when the current accumulated duration reaches the normal starting duration of the firmware and the firm