topic Re: Problem with Guest Access DHCP in Wireless

Problem with Guest Access DHCP

josh.heller — Sat, 03 Jul 2021 22:31:06 GMT

I've got an internal (foreign) controller configured with both our internal SSID, as well as with a guest SSID. The controller is anchored to a DMZ-based guest controller. mping and eping all work, and clients can associate to the guest controller. They cannot, however, get a DHCP address.

DHCP is hosted on the anchor controller. The anchor controller has a management interface, and the WLAN is associated with that management IP. The DHCP scope is within the management interface network.

When a client associates, here's what a debug on the anchor controller shows:

Mon Mar 10 08:42:13 2008: 00:1b:63:07:54:96 DHCP received a REQUEST from Gateway 172.19.229.4 -- bouncing to local DHCP server.

Mon Mar 10 08:42:13 2008: 00:1b:63:07:54:96 DHCP sending to local dhcp server (172.19.229.4:67 -> 192.168.1.5:1067, len 300)

Mon Mar 10 08:42:13 2008: dhcpd: Received 300 byte dhcp packet from 0xac13e504 172.19.229.4:67

Mon Mar 10 08:42:13 2008: Dropping packet from 172.19.229.4 (unable to match to a dhcp scope)

Note that 172.19.229.4 is the management interface of the inside controller, and 192.168.1.5 is the address of the management IP of the anchor controller. Any ideas?

Re: Problem with Guest Access DHCP

sabhasin — Tue, 11 Mar 2008 04:12:12 GMT

Could you provide the output of:

1. show dhcp detailed '

2. show interface detailed - of the vlan interface to which the guest SSID is mapped to

3. show wlan

Re: Problem with Guest Access DHCP

josh.heller — Tue, 11 Mar 2008 14:42:42 GMT

Hi - turns out that its a bug in the 5.0 software, confirmed by a consulting SE. We've found a workaround, just waiting for new code. Workaround was to put all the controllers in the same mobility group, and just make sure the APs can't contact the 'anchor' controller for registration. Not ideal, but it works.