Multipath routing over two ADSL links

a) configure your interfaces
    # echo "inet 192.168.1.243 255.255.255.0 NONE" > /etc/hostname.em0
    # echo "inet 192.168.42.17 255.255.255.224 NONE" > /etc/hostname.em1

b) configure your default route.
It is not possible to use /etc/mygate for both routes so we use the "!" in /etc/hostname.*
    # echo "!route add default 192.168.1.1 -mpath" >> /etc/hostname.em0
    # echo "!route add default 192.168.42.31 -mpath" >> /etc/hostname.em1

c) enable multipath routing
    # echo "net.inet.ip.multipath=1" >> /etc/sysctl.conf

d) minimal nat rules for pf(4)
    set state-policy if-bound
    nat pass on em0 from any to any -> (em0)
    nat pass on em1 from any to any -> (em1)