In an example, there is disclosed a network switch or other computing apparatus comprising: an ingress interface; a plurality of egress interfaces; and one or more logic elements, including at least a content addressable memory (CAM), comprising a channel selection engine to provide persistent channel selection comprising: receive a packet on the ingress interface; inspect a layer 2 (L2) attribute of the packet; lookup the L2 attribute in the CAM; and assign the packet to an egress interface communicatively coupled to a network service.