It is an NP-complete problem in the Hadoop system for minimum task completion time. Recently, many studies propose improvement schemes, but these schemes can still be enhanced. Therefore, in this paper, we proposed a bandwidth-aware rescheduling (BARE) mechanism in the software-defined network (SDN)-based data center networks. BARE uses the feature of the SDN to collect the global information, sorts out the locality data process, performs the task split, and executes the rescheduling mechanism for reducing the task completion time. Finally, we use the simulation to prove our scheme. The performance results show that our scheme outperforms other existing schemes.