Communication apparatus includes multiple interfaces configured to be connected to respective links in a packet data network. Switching circuitry in the apparatus is coupled between the interfaces and is configured to receive, via a first interface among the multiple interfaces, an adaptive routing notification (ARN) requesting that a specified flow of packets from a given source to a given destination in the network be rerouted. The switching circuitry is configured, upon verifying that the first interface serves as an egress interface for the packets in the specified flow, to reroute the specified flow through a different, second interface among the multiple interfaces when there is an alternative route available in the network from the second interface to the given destination, and after finding that there is no alternative route available from any of the interfaces to the given destination, to forward the ARN to a plurality of the interfaces.