The elastic wireless local-area network (WLAN) system has been proposed as an adaptive and elastic WLAN system to traffic load changes in the network. Using Linux PCs, we implemented a testbed for this system that collects necessary information for the Access-Point (AP) aggregation algorithm to determine the activation/deactivation of APs by using Linux commands. Then, it controls the active APs and the associations of hosts based on the algorithm output. In this paper, we present performance evaluations of this elastic WLAN system testbed in two network scenarios in our building.