We consider a pragmatic multi-layer capacity planning approach for an IP over optical network, which builds on existing planning practices. We first describe a router bypass process that considers the real impact of the IP layer topology change, given the actual behavior of the IP layer, leveraging a commercial IP planning tool. We then consider the design and cost impact of several multi-layer restoration schemes. We compute the savings achieved on two real-world core network models. The resulting savings are similar for both networks and are very promising.