/ip firewall mangle
add action=mark-routing chain=prerouting disabled=no new-routing-mark=\
con_rede1 passthrough=no src-address=192.168.0.0/24
add action=mark-routing chain=prerouting disabled=no new-routing-mark=\
con_rede2 passthrough=no src-address=10.10.10.1
/ip firewall nat
add action=masquerade chain=srcnat disabled=no \
out-interface="interface que entra o modem 1"
add action=masquerade chain=srcnat disabled=no \
out-interface="interface que entra o modem 2"
/ip route
add comment=REDE1 disabled=no distance=1 dst-address=0.0.0.0/0 gateway=192.168.27.1
routing-mark=con_rede1 scope=30 target-scope=10
add comment=REDE2 disabled=no distance=1 dst-address=0.0.0.0/0 gateway=10.1.1.1
routing-mark=con_rede2 scope=30 target-scope=10