Freebsd create a lagg failover interface to switch between ethernet and wifi
Freebsd configure the wireless device as a secondary which is only used when the Ethernet connection is not available.
With #lagg(4), it is possible to configure a #failover which prefers the Ethernet connection, while maintaining the ability to transfer data over the #wireless connection.
This is achieved by overriding the Ethernet interface’s #MAC address with that of the wireless interface.
#Freebsd #Handbook
Example 3. Failover Mode Between Ethernet and Wireless #Interfaces
docs.freebsd.org/en/books/handbook/advanced-networ…
Greg A. Woods mag das.