Drag the reasons for AP onboarding failures on the left to the corresponding troubleshooting operations...

According to the Huawei documents and resources, the troubleshooting operations for the AP onboarding failures are as follows:

APS fail to be authenticated by the WAC: Whitelist the APS. The WAC can authenticate APs based on their MAC addresses or SNs. If an AP is not whitelisted on the WAC, it cannot be authenticated and onboarded.

License resources on the WAC are insufficient: Expand the license capacity. The WAC can manage a limited number of APs based on its license. If the license resources are insufficient, some APs cannot be onboarded.

APS fail to obtain IP addresses: Check the DHCP server. The APs need to obtain IP addresses from a DHCP server before they can communicate with the WAC. If the DHCP server is not configured or reachable, the APs cannot obtain IP addresses and onboard.

APS fail to ping the WAC: Check the network between the WAC and APS. The APs need to ping the WAC to discover its IP address and establish a CAPWAP tunnel. If there is a network problem between the WAC and APs, such as incorrect VLAN configuration or firewall blocking, the APs cannot ping the WAC and onboard.

Therefore, APS fail to be authenticated by the WAC - c, License resources on the WAC are insufficient - b, APS fail to obtain IP addresses - d, APS fail to ping the WAC - a is the correct answer. References: : https://support.huawei.com/enterprise/en/doc/EDOC1100158948/9a0d5c37/ap-onboarding-failures