In this paper we present a reconfigurable routing algorithm for a 2D-Mesh Network-on-Chip (NoC) dedicated to fault-tolerant, Massively Parallel Multi-Processors Systems on Chip (MP2-SoC). The routing algorithm can be dynamically reconfigured, to adapt to the modification of the micro-network topology caused by a faulty router. This algorithm has been implemented in a reconfigurable version of the DSPIN micro-network, and evaluated from the point of view of performance (penalty on the network saturation threshold), and cost (extra silicon area occupied by the reconfigurable version of the router).