Unexpected BPDU on 2950T-48 Switch

[keithjohnson_va]

I received the foolowing error messages on a port on a 2950T- 48 Catalyst Switch:

Description: Fa0/42: Unexpected BPDU received. Port has been Disabled

Recommendation: Check Configuration of the switch, also make sure devices connected to the switch. Enable this port again.

Any ideas what caused this error?

Thanks!

[sourabhagarwal]

There can be many reasons which could have caused this.

check this URL to get more information.

http://book.itzero.com/read/cisco/0512/Cisco.Press.CCNP.Practical.Studies.Switching.Oct.2003.INTERNAL_html/1587200600/ch10lev1sec3.html

hope it helps ... rate if it does ....

[keithjohnson_va]

Hey, The link does not open (it times out). Any other thoughts?

Thanks!

[glen.grant]

Sounds like the switch has bpdu guard enabled and some unauthorized person tried to plug in an unauthorized switch on that port which the switch would then disable .

[keithjohnson_va]

Hi! Thanks for your response...

The bpdu guard is not enabled for that particular port which has been disabled.

Any other thoughts? Thanks!

[bjkelley]

You might be running BPDU guard with is on by default on some on the switches to protect your network from going down because of a STP loop. Look the interface that is and see if BPDU guard is enable and if it is disable it.