hwWlanCapwapIpv6Enable 1.3.6.1.4.1.2011.6.139.9.2.4

Work mode of capwap source. It can be set ipv4(1): capwap source just can be configed to ipv4 source. ipv6(2): capwap source just can be configed to ipv6 source. doubleStack(3): capwap source can be configed to ipv4 and ipv6 source at the same time.