The MLAG peer switches synchronize MAC address table to each other using MAC synchronization message. Only when MLAG neighbor state changes to ESTABLISHED and there is a change in the MAC table, the MAC Sync message will be sent.
To check whether the MAC address tables on both peer devices are consistent, use run show mac-address table command to show MAC address table on each MLAG peer device. A MAC address entry contains the VLAN ID, destination MAC address, entry type, aging time and outbound interface.
For details about how MAC tables are synchronized between the MLAG peer devices, see section MAC Synchronization in Principle of MLAG.
For example, when showing MAC address table on each MLAG peer devices after the system automatically completed MAC synchronization, the MAC address should be synced to each other on the MLAG peer devices.