Systems and methods for supporting redundant independent networks in a high performance computing environment. A method can provide, at a computer comprising one or more microprocessors, one or more switches, one or more racks, each of the one or more racks comprising a set of the one or more switches, each set of the one or more switches comprising at least a leaf switch, a plurality of host channel adapters, at least one of the plurality of host channel adapters comprising a firmware and a processor, and a plurality of hosts. The method can provision two or more rails, the two or more rails providing redundant connectivity between the plurality of hosts. The method can isolate data traffic between the plurality of hosts to a rail of the two or more rails.