In a VRRP HSB scenario, if the VRRP preemption delay is set to a small...

According to the Huawei documents and resources, the VRRP preemption delay is the time that an AC waits before preempting another AC with a lower priority. If the VRRP preemption delay is set to a small value, the following problems may occur after a master/backup switchover:

B. A master/backup switchback is triggered too quickly. If the master AC recovers soon after a switchover, it may preempt the backup AC again and become the master AC.  This may cause frequent switchovers and affect network stability 1 .

C. Backup information is incomplete. If the backup AC takes over services from the master AC too quickly, it may not have received all the data sy nchronized from the master AC through HSB.  This may cause service interruption or data loss 2 .

Therefore, B and C are the correct answers. References:  1 : https://support.huawei.com/enterprise/en /doc/EDOC1100064368/80fc2ebd/example-for-configuring-vrrp-hsb  2 : https://support.huawei.com/enterprise/en/doc/EDOC1100096325/1a753937/vrr p-hsb-configuration