A.If the master and backup switches are still in the same stack system after the stack is split, the slave switches separated from the original master and backup switches will re-elect the master and backup transfer machines due to the timeout of the protocol packets.

B.After the stack splits, the MAC addresses of the two stacking systems will definitely change immediately

C.After the split, multiple stack systems will have the same IP address and MAC address. To avoid network failures, the stack will perform MAD detection. The party that fails the MAD detection competition will close all physical ports except for reserved ports.

D.If the main and standby switches are in two stacking systems after the stack is split, the stack system where the original main switch is located will update the topology and re-designate the standby switch. The original standby switch will be promoted to the master in the new stacking system, and the new standby switch will be elected at the same time