Secondary Route

Hello,

Looking to get some assistance with the best way to route traffic at one of our remote offices. We currently have Comcast Business Class internet for all general internet traffic. We also have Comcast ENS (Basically MPLS) for internal traffic. On our Layer 3 Router, I have configured our internal networks to hop over the ENS interface. All other traffic (0.0.0.0/0) is set to go over the Comcast Business connect and is the gateway of last resort.

Ultimately, I'd like to have all traffic route over ENS if the business class connection goes down. What is the most efficient way to make this happen? Right now, presumably, I'd have to connect to the Layer 3 switch and change the 0.0.0.0/0 route.

Thank you!