Flex links is a network switch feature in Cisco equipment which enables redundancy and load balancing at the layer 2 level.
The feature serves as an alternative to Spanning Tree Protocol or link aggregation.
[citation needed] Load balancing in Flex links work at VLAN level.
[2] Both the ports in the Flex link pair can be made to forward traffic simultaneously.
Mutually exclusive VLANs are load sharing the traffic between the Flex link pairs.