terminal connect wifi not stable，always disconnect

terminal use wireless connection to ap，ap use wire connection to core-sw，core-sw running as the gateway and DHCP relay，core-sw running as vrrp,ac running as central-forwarding（means all service traffic will go through capwap tunnel to ac firstly）

customer feedback that the wifi signal is not stable，terminal always connect a few seconds then disconnect，after some common wireless optimization methods（user-isolation，forbid low speed and so on），the issue still there.

configure service vlan at ac，and set the ip address as dhcp allocate mode，after a few seconds，we find that ac can get the ip address of dhcp，but when we display arp，there is not arp of the gateway，which means layer 3 traffic will fail to send to core-sw.

core-sw belong to third party，after we check its configuration，we find that dhcp allocate the vrrp virtual ip address of the vlan-interface of core-sw，and core-sw didnt replay the arp request.

bcz core-sw side cant solve the arp response issue,we let dhcp side to change the gateway as the physical ip address of vrrp，then it works，terminal can get the arp of gateway，and connection is stable.