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New Member

AP 1100 not passing DHCP requests for NonDefault Vlan

Hi group.

Rather new to wireless here.

The current Hardware we are using are Cisco 350series Pcmcias, 1100 AP, Windows 2000 Radius server using MS AIS ( also our dhcp server)

We are trying to setup a wireless network where we have two vlans. One vlan would authenticate using Network Eap to our AD using Windows 2000 AIS and another vlan that would use Open Authentication.

Vlan1 SSID is named NetEAP and Vlan2 SSID is named Open.

The situation we have is that no matter what default Vlan I choose , either Vlan1(NetEAP) or Vlan2(Open) in the APs 1100 config , the other NonDefault vlan will not issue dhcp requests to the server but will still authenticate to AIS. For example if i set the 1100 AP default Vlan to Vlan2 and configure the test laptop ACU SSID to Open(vlan2) , the laptop will authenticate to the AIS server and pick up a IP address. Now if i keep the 1100 AP default Vlan set to Vlan2 and change the test Laptops ACU SSID to NetEap(vlan1) the laptop still authenticates to our AIS server but can not pick up an IP address. I put a sniffer on the line during this process and was unable to see a DHCP request.

I could be very off here but I tried to apply a IP filter so that 1100 AP could fwd DHCP requests for Vlan1(NetEap) while the Default Vlan on the 1100 AP was Vlan2. I fwded port 17,67,68 and Ip address subnet Like i said, i could be way off here but those are the ports and address the sniffer picked up when the dhcp requests were accepted. This did not work so i am scratching my head alittle.

Sorry if this if confusing. Hopefully someone has had a similar experiance and can help me out. Thanks for reading.


  • Security and Network Management

Re: AP 1100 not passing DHCP requests for NonDefault Vlan

Requests per second The DHCP server hardware and software must be able to accommodate the projected number of new DHCP requests per second that will be offered by introducing WLANs. If the DHCP servers are overburdened, wireless users will not be able to acquire DHCP addresses, denying LEAP users from gaining IP connectivity after authentication.

New Member

Re: AP 1100 not passing DHCP requests for NonDefault Vlan


Thanks for the reply. I do understand your point, however the tests i am performing are on a 4 node experimental lan. All that is on the network is our win2000 dhcp/Ias server, Aironet 1100 Ap , 2 laptops ( one wireless and one wired). Also when the Default vlan is set to SSID guest on the AP and the laptop with ACU i am able to see the request by sniffing the wired side. I see Source address Destination Dhcp discover. Now when i change only the laptops SSID to Staff, the laptop associates to the AP but the DHCP requests do not pass threw AP to the wired side.

I am not familiar either with Ciscos CLI so i am scratching my head with this one.