Cisco 1811w Wifi suddenly stopped working

Posted on 2012-08-16
Last Modified: 2012-08-17

 We have a Cisco 1811w installed in one of our branch office locations. We've had wireless setup on the dot11 0 interface working for a couple years now.

All of a sudden the SSID is no longer available. Unfortunatly we don't have the resource's to check if there's infact nothing coming out of the interface, for example beacons.

There were no router configuration change or physical changes that would have invoked this. The output of "show interface dot11radio 0" looks good except for "Last input 03:27:26, output 03:26:25, output hang never" I had issued a "clear counters" command on this interface maybe 45 minutes before grabbing the below output.

Dot11Radio0 is up, line protocol is up
  Hardware is 802.11G Radio, address is 001f.6c98.7a70 (bia 001f.6c98.7a70)
  Description: 2.4Ghz radio
  MTU 1500 bytes, BW 54000 Kbit/sec, DLY 1000 usec,
     reliability 180/255, txload 1/255, rxload 1/255
  Encapsulation 802.1Q Virtual LAN, Vlan ID  1., loopback not set
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 03:27:26, output 03:26:25, output hang never
  Last clearing of "show interface" counters 01:01:05
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 15
  Queueing strategy: fifo
  Output queue: 0/30 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     0 packets input, 0 bytes, 0 no buffer
     Received 77 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 input packets with dribble condition detected
     20 packets output, 3312 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 unknown protocol drops
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out

How do we test to see if this dot11radio interface is dead?
Question by:mharmon_geo
    LVL 36

    Accepted Solution

    it could be a hardware failure.

    have you tried rebooting the router ?

    Author Comment

    Unfortunatly at the time I made this post I didn't have the ability to reboot the router as it was also the gateway for for our executive staff. I did manage to reboot after hours last night and that brought the wireless back... Not sure if this is somehting that will occur again.

    What would we look at to determine any issues that may result in this happening again? I.E. memory leak, overflow's.... Anyone with helpful information on that gets the points!
    LVL 36

    Expert Comment

    if it was me, I'd open a TAC case, but I'm guessing that you don't have smartnet on it.

    if you have CCO access you could look at the bug toolkit, if you don't have CCO access you could post your exact IOS version and somebody might have a look for you.

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