Which of the following description about the operation of the software are correct? (Multiple choice)
A . Before performing important software operation tasks, you need to submit a software operation application and get approval of the customer and Huawei service manager.
B . Whenever the equipment/system is found to be operating abnormally, it is necessary to communicate with the equipment supplier or relevant responsible person in time to detect or prevent the failure as soon as possible.
C . Develop a system fallback mechanism. If unexpected results are produced, start the system fallback mechanism as soon as possible, end the work, and re-enact the implementation plan.
D . After the on-site operation is completed, the customer site logbook must be updated in a timely manner.
Answer: ABCD