1. / ip address
add address=192.168.37.1/24 network=192.168.37.0 broadcast=192.168.37.255 interface=LAN
add address=19.74.30.2/24 network=19.74.30.0 broadcast=19.74.30.255 interface=ADSL2
add address=12.25.20.2/24 network=12.25.20.0 broadcast=12.25.20.255 interface=ADSL1
/ ip firewall mangle
add chain=input in-interface=ADSL1 action=mark-connection new-connection-mark=ADSL1_conn
add chain=input in-interface=ADSL2 action=mark-connection new-connection-mark=ADSL2_conn
add chain=output connection-mark=ADSL1_conn action=mark-routing new-routing-
mark=to_ADSL1
add chain=output connection-mark=ADSL2_conn action=mark-routing new-routing-
mark=to_ADSL2
add chain=prerouting dst-address=19.74.30.0/24 action=accept in-interface=LAN
add chain=prerouting dst-address=12.25.20.0/24 action=accept in-interface=LAN
add chain=prerouting dst-address-type=!local in-interface=LAN per-connection-classifier=both-
addresses:2/0
action=mark-connection new-connection-mark=ADSL1_conn passthrough=yes
add chain=prerouting dst-address-type=!local in-interface=LAN per-connection-classifier=both-
addresses:2/1
action=mark-connection new-connection-mark=ADSL2_conn passthrough=yes
add chain=prerouting connection-mark=ADSL1_conn in-interface=LAN action=mark-routing new-
routing-mark=to_ADSL1
add chain=prerouting connection-mark=ADSL2_conn in-interface=LAN action=mark-routing new-
routing-mark=to_ADSL2
/ ip route
add dst-address=0.0.0.0/0 gateway=19.74.30.1 routing-mark=to_ADSL1 check-gateway=ping

2. add dst-address=0.0.0.0/0 gateway=12.25.20.1 routing-mark=to_ADSL2 check-gateway=ping
add dst-address=0.0.0.0/0 gateway=19.74.30.1 distance=1 check-gateway=ping
add dst-address=0.0.0.0/0 gateway=12.25.20.1 distance=2 check-gateway=ping
/ ip firewall nat
add chain=srcnat out-interface=ADSL1 action=masquerade
add chain=srcnat out-interface=ADSL2 action=masquerade