In a switching network, each of a plurality of lower tier entities is coupled to each of multiple master switches at an upper tier by a respective one of multiple links. At each of the multiple master switches, a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier are implemented on each of a plurality of ports. Each of the plurality of lower tier entities implements a respective egress port mapping indicating which of its plurality of RPIs transmits egress data traffic through each of its multiple links to the multiple master switches. In response to failure of one of the multiple links coupling a particular lower tier entity to a particular master switch, the particular lower tier entity updates its egress port mapping to redirect egress data traffic to another of the multiple master switches without packet dropping.