need help with Apple device on DHCP

[leonxjm]

I turned a TP-Link wireless route's DHCP off, use it as a switch. It connected to Cisco 4331 router. As a WIFI spot for mobile phones, it works normally on Android cells, but not for Apple devices. I keep receiving these messages: *Oct 16 09:43:06.140 lqjc: DHCPD: Sending notification of ASSIGNMENT FAILURE: *Oct 16 09:43:06.140 lqjc: DHCPD: htype 1 chaddr f4cb.5220.bc46 *Oct 16 09:43:06.140 lqjc: DHCPD: remote id 020a0000ac1029fe04020000 *Oct 16 09:43:06.140 lqjc: DHCPD: interface = Vlan20 *Oct 16 09:43:06.140 lqjc: DHCPD: class id 616e64726f69642d646863702d382e302e30 *Oct 16 09:43:06.140 lqjc: DHCPD: Sending notification of ASSIGNMENT_FAILURE: *Oct 16 09:43:06.140 lqjc: DHCPD: due to: CLIENT CHANGED SUBNET *Oct 16 09:43:06.140 lqjc: DHCPD: htype 1 chaddr f4cb.5220.bc46 *Oct 16 09:43:06.140 lqjc: DHCPD: remote id 020a0000ac1029fe04020000 *Oct 16 09:43:06.140 lqjc: DHCPD: interface = Vlan20 *Oct 16 09:43:06.140 lqjc: DHCPD: class id 616e64726f69642d646863702d382e302e30 Does anyone know what's going on? It says CLIENT CHANGED SUBNET, but the IP address is assigned by the router, there is no reason to show this message. Also, assign the static IP address on Apple device is not working as well.

[Flavio Miranda]

Hello @leonxjm

 Just to understand, Who is performing DHCP service? Cisco 4331 router ?

Both devices Android and Apple are connected via Wi-Fi to TP-Link wireless and the DHCP is the Ciso 4331 ?

-If I helped you somehow, please, rate it as useful.-

[leonxjm]

Yes, 4331 is performing the DHCP service.

[Flavio Miranda]

Thanks @leonxjm

Just one more question. Which TP-Link model is it?

[Georg Pauwen]

Hello,

try and enable 'ip dhcp conflict logging' on the router that provides the DHCP service...

[Georg Pauwen]

Hello,

ok, I have looked around some more, and this might be an iOS bug. What is the lease time configured ? Make sure it is 4 hours or more. You can also confgure::

ip dhcp client lease 1

which sets the client lease to 1 day.