Cisco default route to two interfaces?

Question

Computer networks

What is the risk of adding default routes to different providers with different metrics? I don't understand what could be wrong?
let's say so
ip route 0.0.0.0 0.0.0.0 10.0.0.1
ip route 0.0.0.0 0.0.0.0 10.0.0.2 50

Answer 1

What is the risk of adding default routes to different providers with different metrics?

The fact that only one will be active.

let's say so
ip route 0.0.0.0 0.0.0.0 10.0.0.1
ip route 0.0.0.0 0.0.0.0 10.0.0.2 50

In this case, if I understand correctly, devices with addresses 10.0.0.1 and 10.0.0.2 are accessible through the same interface. Most likely, the topology is as follows: your device is connected to the switch, routers of providers are also connected to it. This means that if 10.0.0.1 stops working (turns off), the interface will not change its state (remain in the up / up state), unlike schemes with a dedicated interface on the router. Most likely, the route to 10.0.0.1 will remain in the routing table and there will be no "switching" of routes and traffic. To correct the behavior, use ip sla tracking.

Answer 2

Depending on what effect you want to achieve.
Check out this article, even more note habrahabr.ru/post/80717

Answer 3

I will take out in response to the chupasaurus hint :
Police-based routing
- habrahabr.ru/post/101796 - part 1
- habrahabr.ru/post/114197 - part 2