The Handbook, "http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/network-aggregation.html#NETWORKING-LAGG-WIRED-AND-WIRELESS", example 31-3 descripes:
"In this setup, we will treat the wired interface, bge0, as the master, and the wireless interface, wlan0, as the failover interface. The wlan0 was created from iwn0 which we will set up with the wired connection's MAC address. The first step would be to obtain the MAC address from the wired interface:"
In my setup this will not work, and I'm not sure why, probably because of the Zyxel ISP router I have.
I simply used the wireless MAC address instead, to the wired adapter, and everything worked right away.
I will suggest that the documentation mentions that either way around should be tried, if there is problems with this setup ;-).
You could descripe it it as Option 1 and Option 2 ;-)
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