/routing table
add fib name=tounicom

/ip route
add dst-address=0.0.0.0/0 gateway=pppoe-unicom routing-table=tounicom

/ip firewall nat

# 对于默认路由，开启 dst nat 即可
add chain=dstnat in-interface=pppoe-cmcc dst-port=9000 protocol=tcp action=dst-nat to-addresses=192.168.1.8 to-ports=8443

add chain=dstnat in-interface=pppoe-unicom dst-port=9000 protocol=tcp action=dst-nat to-addresses=192.168.1.8 to-ports=8443

/ ip firewall mangle

add chain=prerouting in-interface=pppoe-unicom action=mark-connection new-connection-mark=unicom_con
add chain=output connection-mark=unicom_con action=mark-routing new-routing-mark=tounicom
add chain=prerouting connection-mark=wan2_con src-address=192.168.1.251/32 action=mark-routing new-routing-mark=tounicom

# 为了避免流量被 fasttrack 处理，将以下两条规则加到 fasttrack 之前
/ip firewall filter
add action=accept chain=forward connection-state=established,related src-address=192.168.1.251
add action=accept chain=forward connection-state=established,related dst-address=192.168.1.251