Field Notice: FN - 61082 - Repeater Mode Denies Wireless Client Access

Revised October 04, 2005

December 30, 2002

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NOTICE:

THIS FIELD NOTICE IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTY OF MERCHANTABILITY. YOUR USE OF THE INFORMATION ON THE FIELD NOTICE OR MATERIALS LINKED FROM THE FIELD NOTICE IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS FIELD NOTICE AT ANY TIME.

Products Affected

• AIR-AP1200

• AIR-AP342E2C

• AIR-AP352E2C

• AIR-WGB352C

Problem Description

When an access point (AP) or bridge loses its ethernet connection, its default action is to change to repeater mode. If you are configuring an AP or bridge for the first time and the AP or bridge lacks an ethernet connection, then it interprets this condition as "lost ethernet" and, by default, becomes a repeater. 4800 Series APs and bridges had a different default, as documented in CSCdz48575 and CSCdz57782. In repeater mode, the AP or bridge may refuse to associate WLAN clients making it impossible to configure the AP or bridge using a WLAN client.

Background

Version 12.00T of AP/bridge firmware adds a "lost ethernet" feature that is available on Aironet 4800 Series products and also is available on the Aironet AP 1100, which runs Cisco IOS® software. The feature gives an administrator the ability to select the best action for an AP or bridge to take when it loses the ability to send and receive data over ethernet.

With Version 12.00T of AP/bridge firmware, the default action is to switch to repeater mode. The AP 1100 and Aironet 4800 Series products support a different default action. In repeater mode, the AP or bridge attempts to register (link) to another AP or bridge. If a link can be established, then the AP or bridge with no ethernet connection permits registration of clients. If a link cannot be established, then the AP or bridge with no rthernet connection does not permit registration of clients.

If, when trying to use a WLAN client to configure an AP or bridge that does not have an ethernet connection for the first time, this AP or bridge goes into repeater mode and fails to establish a link with another AP or bridge, then you cannot configure the AP or bridge because it will not permit your WLAN client to associate with it. Similarly, you will be unable to conduct a site survey with an AP or bridge that lacks an ethernet connection and cannot establish a link to another AP or bridge.

Problem Symptoms

The following issues can arise should the access point not have a valid ethernet connection and Repeater Fall Back is enabled.

1. Wireless clients may not be able to establish a radio link to the access point. Repeater access points without a valid link to a root access point will deny registration attempts by wireless clients.

2. Wireless clients may connect to an unintentional network, perhaps on an unintended or unknown wireless network operated by someone else. This can happen if an access point in repeater mode connects to a default access point somewhere else.

3. Site surveyors without a network connection cannot (by default) establish a connection to the access point using a wireless client.

4. Wireless clients may appear to bounce from connected to disconnected within the Aironet Client Utility (ACU) as the client tries to establish a connection and then is denied by the access point in repeater mode. This bouncing could appear to the user as a client problem.

5. Access points powered from a powered injector may appear to the user to have a valid ethernet connection; however; should the other side of the injector (to network) not be connected this fallback mode can be triggered causing confusion as the access point denies clients or becomes a repeater.

6. Users managing the access point using a serial connection may be confused as to why device is in repeater mode.

7. Users wishing to configure the access point using a wireless client before connecting the access point to a network will have difficulty.

8. Wireless clients may experience slower throughput as they hop through the access point operating in repeater mode.

Workaround/Solution

Any of the following solutions will resolve the issue.

1. Connect the access point to a valid ethernet connection before attempting wireless client access.

2. Disable repeater fallback mode either serially or by connecting to a valid network and then browse into the device and disable this feature.

3. To disable fallback mode from the browser (also known as "Loss of Backbone Connectivity Action"), browse into the access point and choose change from Switch to Repeater Mode to No Action.

DDTS

To follow the bug ID link below and see detailed bug information, you must be a registered user and you must be logged in.

DDTS	Description
CSCdz57782	Repeaters claim switching to repeater when parent down
CSCdz48575	Default Lost Ethernet action not appropriate

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods:

• Open a service request on Cisco.com
• By email
• By telephone

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