Wireless, LAN (WLAN)

Document ID: 6323

Contents

Introduction
Prerequisites
      Requirements
      Components Used
      Conventions
Problem
Solution
NetPro Discussion Forums - Featured Conversations
Related Information

Introduction

Cisco IOS® updates have changed the default number of antennas configured on the radio interface of the ubr7200 VXR routers.

Prerequisites

Requirements

Cisco recommends that you have knowledge of these topics:

• Wireless networks

• Radio interface

• Command-line usage

In order to perform the tasks noted in this document, you must have privileged EXEC ("enabled") access on the router you want to examine.

Components Used

The information in this document is based on these software and hardware versions:

• uBR7223/7246/7246VXR platforms

• IOS versions 12.1(5)XM and 12.2(2)T.

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.

Conventions

Refer to Cisco Technical Tips Conventions for more information on document conventions.

Problem

When you upgrade from Cisco IOS Software Release 12.1(5)XM to 12.2(2)T, the default number of antennas in Cisco IOS increases from one to two. If you use and have only one antenna configured in the Headend (HE) running the configuration, when you upgrade and reload the router, you cannot bring the radio interface to an up/up state.

When you issue the no shut command under the radio interface on the HE, you receive this error message:

%CWRMP-4-RF_IF_COMM: Radio2/0, IF-to-RF/ODU2 comm error on
 ODU Controller Reset cmd

Solution

Use this solution to solve the problem.

Complete these steps:

1. Under the radio interface, issue this configuration command:

   radio receive-antennas 1
   

2. The radio interface state changes to up as shown in this output:

   UNII-HE(config-if)# no shut
   Oct 29 22:42:41.451: %LINK-3-UPDOWN: Interface Radio2/0, changed state to
   down
   UNII-HE(config-if)#
   Oct 29 22:42:53.395: %CWRMP-4-RF_IF_COMM: Radio2/0, IF-to-RF/ODU2 comm
   error on ODU Controller Reset cmd
   Oct 29 22:43:03.395: %CWRMP-4-RF_IF_COMM: Radio2/0, IF-to-RF/ODU2 comm
   error on ODU Controller Reset cmd
   Oct 29 22:43:13.399: %CWRMP-4-RF_IF_COMM: Radio2/0, IF-to-RF/ODU2 comm
   error on ODU Controller Reset cmd
   Oct 29 22:43:23.399: %CWRMP-4-RF_IF_COMM: Radio2/0, IF-to-RF/ODU2 comm
   error on ODU Controller Reset cmd
   UNII-HE(config-if)# radio receive-antennas 1
   Oct 29 22:43:48.539: %UBR7200-5-UPDOWN: Interface Radio2/0 Port U0, changed
   state to up
   Oct 29 22:43:48.539: %UBR7200-5-UPDOWN: Interface Radio2/0 Port U1, changed
   state to administratively down
   Oct 29 22:43:48.539: %UBR7200-5-UPDOWN: Interface Radio2/0 Port U2, changed
   state to administratively down
   Oct 29 22:43:48.539: %UBR7200-5-UPDOWN: Interface Radio2/0 Port U3, changed
   state to administratively down
   Oct 29 22:43:49.663: %SYS-5-CONFIG_I: Configured from console by console
   Oct 29 22:43:50.539: %LINK-3-UPDOWN: Interface Radio2/0, changed state to
   up
   Oct 29 22:43:51.539: %LINEPROTO-5-UPDOWN: Line protocol on Interface
   Radio2/0, changed state to up
   
   

NetPro Discussion Forums - Featured Conversations

Related Information

• Cisco uBR7200 Series Universal Broadband Router Wireless Modem Card and Subsystem Installation and Configuration
• Wireless Technology Support Page
• Technical Support & Documentation - Cisco Systems