I have an MPLS network with carrier 1. I am about to install a second MPLS network with carrier 2. Can any direct me on the best approach to configure the routers so that a failure from carrier 1 seamlessly will redirect traffic via carrier 2. And then switch back after carrier 1 is working properly? Are there any FAQs on this subject? Using Cisco 1841, 2811 and 2490 routers.