Huawei Exam H12-321 Topic 18 Question 43 Discussion

The AP periodically sends a Discovery Request packet to check the status of the original primary link. After the link is restored, the AP detects that the link has a higher priority than the currently used primary link and triggers the switchback. To prevent frequent network switching, the AC is notified of the active/standby switchover. The AP sends the data service of the STA to the newly upgraded AC.