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Wireless connection issues (851W)

Hi all,

I have several cisco routers 851w deployed in diferent offices to implement and support local wireless networks.

Every router is configured the same:

  • IOS 12.4(15)T10 (c850-advsecurityk9-mz.124-15.T10.bin)
  • 1x SSID with WPA2 AES
  • no cdp
  • no dot11 aironet extensions

The following behaviour has been observed several times, with laptops from different brands (Dell, HP and Lenovo). Hopefully diferent wireless chipsets.

The user is accessing diferent machines (remote desktop, www, McAfee ePO...) and suddendly loses connection to one server.

All the rest is available, only that server is unreachable. From a wired laptop we never lose access, from a wireless laptop we do (same IP /24 network).

After this happens the most successful way to recover access is to restart the laptop wireless card.

Has anyone have any ideas?

Secondly, how should I debug the situation? How can I check if the wireless network is having any type of conflit?

I already searched for the presence of other networks (no conflict found), I tryed changing channels, deactivating WPA... I keep having connection issues.

It's like after a while the router stops forwarding/processing specific connections. Can this be a security feature activated by mistake?

Best regards,

Francisco Sanches

Everyone's tags (5)
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Re: Wireless connection issues (851W)

Is this a flat network or do you have multiple vlans setup?  If you are seeing this with all different devices, then you can eliminate that out the picture... most of the time.  So basically they are unable to get to a certain server but still has network connectivity?  Tough to say... I would either try to update on client device driver and see if that helps, if not, try a different code to see if that is your issue.  I'm running a 871W at home, but still on the 12.3 code.

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