?
Solved

Err-disabled stat on cisco switch port

Posted on 2007-03-19
4
Medium Priority
?
4,917 Views
Last Modified: 2008-04-05
I am intermittently having ports shut down on switches throughout my company. The switches I have are Cisco 3560 catalyst.  When I check the port it is in an err-disable state.  I can bring the port up by doing the shutdown no shutdown command on the interface.  When I check the status on the port to see why it went down the reason listed is bpduguard.  Bpduguard is enabled on the port. But my understanding was bpduguard detected bpdu packet.  I though bpdu packets only came from devices like switches.  The devices that are connected to the ports that go into the err-disable state are computers (Dell 9200).  Why would the switch think that the computers are sending out bpdu packets.
      
Any insight would be most appreciated.
0
Comment
Question by:SHAX
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
4 Comments
 
LVL 50

Expert Comment

by:Don Johnston
ID: 18751997
SOMETHING caused a BPDU to come in that port. It could be that a user connected an unauthorized switch or maybe a cable got connected so that a loop was created.

The only time I've seen a computer generate a BPDU is if has multiple NIC's and it is configured to bridge the traffic between the NICs.

It sounds like some investigating is in order. :-o
0
 

Author Comment

by:SHAX
ID: 20251522
*****Updated info for original post.*****  The NIC that we are seeing the BPDU's from are the Intel 82566 DC Integrated NIC in the Dimension 9200 desktop models.  As to the comment by donjohnson, the users are not plugging in unauthorized switches, nor have any cabling changes been made.  Thanks for the suggestion, but that isn't the case in this situation.  Any other comments and suggestions will be welcome.

Thanks
0
 
LVL 50

Assisted Solution

by:Don Johnston
Don Johnston earned 2000 total points
ID: 20253594
Do these PC's have wireless cards? If so, then the BPDU's could be arriving at the PC over the wireless link and the PC then passes it on to the switch.

The only way a PC will send out BPDUs:

1) There is more than on network interface on the PC and the PC is bridging the NICs.
2) The PC has a protocol analyzer and has previously captured BPDUs and is now sending them back out.
3) The PC is running a bridging service thereby making it a bridge.

It's got to be one of those.
0
 

Accepted Solution

by:
SHAX earned 0 total points
ID: 20564904
Looks like the problem was a magic packet/wake on lan setting in the network card.  Once that was turned off I have not seen any more problems
0

Featured Post

Connect further...control easier

With the ATEN CE624, you can now enjoy a high-quality visual experience powered by HDBaseT technology and the convenience of a single Cat6 cable to transmit uncompressed video with zero latency and multi-streaming for dual-view applications where remote access is required.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I see many questions here on Experts Exchange regarding switch port configurations and trunks. This article is meant for beginners in the subject to help to get basic knowledge about Virtual Local Area Network (VLAN (http://en.wikipedia.org/wiki/Vir…
Arrow Electronics was searching for a KVM  (Keyboard/Video/Mouse) switch that could display on one single monitor the current status of all units being tested on the rack.
NetCrunch network monitor is a highly extensive platform for network monitoring and alert generation. In this video you'll see a live demo of NetCrunch with most notable features explained in a walk-through manner. You'll also get to know the philos…
In this brief tutorial Pawel from AdRem Software explains how you can quickly find out which services are running on your network, or what are the IP addresses of servers responsible for each service. Software used is freeware NetCrunch Tools (https…

777 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question