参考HA说明吧
http://www.cisco.com/c/en/us/td/docs/wireless/controller/8-3/config-guide/b_cg83/b_cg83_chapter_0101010.htmlThe following are some guidelines for high availability:
We recommend that you do not pair two controllers of different hardware models. If they are paired, the higher controller model becomes the active controller and the other controller goes into maintenance mode.
We recommend that you do not pair two controllers on different controller software releases. If they are paired, the controller with the lower redundancy management address becomes the active controller and the other controller goes into maintenance mode.