The smart-link flush send vlan command enables the active interface in an Eth-Trunk interface in manual 1:1 master/backup mode to send Smart Link Flush packets.
The undo smart-link flush send command disables the active interface in an Eth-Trunk interface in manual 1:1 master/backup mode from sending Smart Link Flush packets.
By default, the active interface in an Eth-Trunk interface in manual 1:1 master/backup mode is disabled from sending Smart Link Flush packets.