无线wifi获取ip地址时而很慢的问题？

ac上配置的本地转发，dhcp在核心交换机上，核心与poe交换机都是trunk允许所有通过。无线根据不通的地点划分了3个网段，vlan分别是103、203、303.
现在我连接wifi有时候会获取ip地址很慢,大概需要一分钟以上，甚至更久，但是一但获取到了ip再忘记wifi再重新连接就能秒获取ip。这种获取ip很慢的情况会不定时出现。
我想问问这种问题一般有哪些原因？需要怎么处理？以下是ac和poe的配置
AC配置
vlan 1
#
vlan 100 to 101
#
vlan 103
#
vlan 203 to 303
#
wlan service-template slgf
 description wu
 ssid SLGF
 vlan 103
 client forwarding-location ap vlan 203
 client forwarding-location ap vlan 303
 quick-association enable
 akm mode psk
 preshared-key pass-phrase cipher $c$3$d/UZQp69plVcEwBj4X8Crl0air0A97W3Wl5w
 cipher-suite tkip
 security-ie wpa
 service-template enable
#
interface Vlan-interface100
 ip address 172.20.0.2 255.255.255.0
#
interface Vlan-interface101
 ip address 172.21.0.5 255.255.255.0
#
interface GigabitEthernet1/0/7
 port link-mode bridge
 port link-type trunk
 port trunk permit vlan all
#
 netconf soap http enable
#
 ip http enable
 ip https enable
#
 smartmc tm username admin password cipher $c$3$aOYFicfQMVAQrPbeTJ2Wtk7mV2xJZN S enable
#
 wlan auto-ap enable
 wlan auto-persistent enable

poe交换机配置
vlan 1
#
vlan 100 to 101
#
vlan 103
#
vlan 203
#              
vlan 303
#
 stp bpdu-protection
 stp global enable
#
interface NULL0
#
interface Vlan-interface1
#
interface Vlan-interface101
 ip address 172.21.0.24 255.255.255.0
#
interface range GigabitEthernet1/0/1 to GigabitEthernet1/0/24
 port link-type trunk
 port trunk permit vlan all
 port trunk pvid vlan 100
 undo stp enable
 stp edged-port
 poe enable
#
interface GigabitEthernet1/0/28
 port link-type trunk
 port trunk permit vlan all
#

ac挂在核心交换机上，核心交换机直接连接poe交换机，poe下连接ap