Cisco WLAN 2100 series Controller Troubleshooting

Posted on 2012-08-23
Last Modified: 2012-09-12
I have a Cisco WLAN 2100 series controller that keeps disconnecting from the network then reestablishing itself on the network about 10 minutes later. I would like to see what is causing this issue but don't know where to start really. I have attached the console cable to the device and have connected it to a laptop running a hyper-terminal client. I can log into the device but that is it. how can I "Watch" the device through the console so I can see why it is disconnecting\crashing all the time?
Question by:tparus
    LVL 13

    Expert Comment

    Force the ethernet port to 100Mb/s full on the switch.  It's probably an autoneg problem.
    LVL 10

    Accepted Solution

    Well, hard to say what the cause is. I'd first go to see if there are any log messages that might tell you someting about the cause of your trouble. As the buffered logging probably is switched of it might be useful to enable it so you don't have to sit next to your PC all the time. See how to enable the logging on your controller.

    The idea with the negotiation of the ethernet is a good one, however by just setting it to a static value on one side the chance is 50:50 that you solve the problem or you create a new one. Have a look at the settings on both sides; if you see on the switch that it gets someting like A-100 a-full then you don't have to change anything - if you see anything like a-half then you might want to check the settings on the controller.

    You might want to post any log output from the controller or from the switch that can give some indications where to continue your search.

    Author Comment

    Ok, I have connected a cable to the console port and connected the other end to a laptop and it has been running all day. The device has encountered issues now twice and it says if I want to see the crash log I can go to this location. /mnt/application/mwar_dump1.crash but where is that located and how to I get to it. I am unfamiliar with Cisco commands so any help would be great. Also, once I get this log how do I find out what is causing the crash? If I post it can someone read it for me?

    Thanks and sorry for being such a nube on this.

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