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Wireless clients unable to obtain IP address via DHCP from server attached to Ethernet interface

Configuration:

Cisco 2811 router with HWIC-AP-G-A  802.11B/G WIC card installed. The router is configured with a bridge group that includes both the wired interface and the wireless interface. The wired interface (FE0/0) has a Windows 2003 DHCP server connected to it. All computers connected to the wired LAN obtain an IP address from DHCP server without a problem.

PROBLEM: Wireless clients associate with the wireless interface without a problem, but are not receiving the DHCP IP address from the server.

Router configuration is as follows:

interface Dot11Radio0/3/0
 no ip address
 !
 encryption mode ciphers tkip
 !
 ssid TEST
    authentication open
    authentication key-management wpa
    wpa-psk ascii 7 <blah>
 !
 speed basic-1.0 basic-2.0 basic-5.5 6.0 9.0 basic-11.0 12.0 18.0 24.0 36.0 48.0 54.0
 station-role root
 bridge-group 1
 bridge-group 1 subscriber-loop-control
 bridge-group 1 spanning-disabled
!
interface BVI1
 ip address 10.109.0.254 255.255.255.0
 ip helper-address 10.109.0.10
 ip nat inside
 ip virtual-reassembly

interface FastEthernet0/0
 no ip address
 ip virtual-reassembly
 duplex auto
 speed auto
 bridge-group 1
 bridge-group 1 subscriber-loop-control
 bridge-group 1 spanning-disabled

Here is the wireless association:
------------------------------------
router#sho dot11 assoc

802.11 Client Stations on Dot11Radio0/3/0:

SSID [TEST] :

MAC Address    IP address      Device        Name            Parent         State    
0019.7e60.a84f 169.254.99.232  4500-radio    BVI-KYRIA2      self           Assoc    


Others:  (not related to any ssid)
--------------------------------------------

Here is the sho ver:

--------------------------------------------
router#   sho ver
Cisco IOS Software, 2800 Software (C2800NM-ADVIPSERVICESK9-M), Version 12.4(11)T, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2006 by Cisco Systems, Inc.
Compiled Sat 18-Nov-06 17:16 by prod_rel_team

ROM: System Bootstrap, Version 12.4(1r) [hqluong 1r], RELEASE SOFTWARE (fc1)

router uptime is 6 days, 8 hours, 17 minutes
System returned to ROM by power-on
System restarted at 08:18:47 GMT Tue Oct 23 2007
System image file is "flash:c2800nm-advipservicesk9-mz.124-11.T.bin"
-------------------------------------------------

This most likely has to do with the wireless card not flooding DHCP packets from the wireless clients to the wired interface.

Please help.

Avatar of mikebernhardt
mikebernhardt
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You didn't provide enough config to see the radio interface. does it definitely have "bridge-group 1" on it? Also there's no need for the ip helper-address on the BVI interface. The server should hear any broadcasts on the local LAN, which should include the wireless.

If you give your wireless client a static address, does it work? that will confirm whether you are properly associated.
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ihsupport

ASKER

Mike,

Please re-read my original post. The entire wireless interface config is in there. The first line is "interface Dot11Radio0/3/0" and the last line is "bridge-group 1 spanning-disabled". As you can see, I definitely do have "bridge-group 1" on it. The ip-helper address command was added by me out of desperation in order to see if it makes any difference. It obviously did not.

When I give my wireless clients a static IP, they can ping the default gateway (BVI 1) adddress. This confirms that they are properly associated. The problem seems to be very simple - the router is not allowing ANY traffic between the wireless network and the wired network, which are both members of the same bridge group. Thats why DHCP for wireless clients is not working either, as the DHCP server is on the wired segment.
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mikebernhardt
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