Can you do this with route tagging?

[konaruegi]

I’m working remotely with a router that has three interfaces. Two go to the ISP, one to the firewall. One ISP connection will be gone soon, but I need them to both work for a little while.

I configured a subinterface on the router and firewall interfaces to handle the second ISP connection, and things seem to work ok.

Now I need a way to tell the router to send packets out the same interface they came in on. Could I do that with route tagging? I’m not running BGP or anything like that. I found that ASAs will route that way if you configure a second default route with a higher distance, but routers seem to treat it as a failover route.

[MHM Cisco World]

start from ASA, 
divide the LAN into two subnet 
use PBR and make each PBR point toward on ISP 

in router config 
three static route 
one for subnet Before split 
two other for each split new subnet and each one point toward one subinterface of OUT of ASA

this make ASA forward via one subinterface OUT and make router return the traffic back via same path.