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New Member

stp ports leaving and joining bridge

I been having trouble with my 4006 switch, a lot of ports are leaving and joinging bridge. I am currently using STP on all my 4000 switches.

New Member

Re: stp ports leaving and joining bridge

This is a common occurance as devices are turned on and off on the network. Are you having people complain of intermittent connectivity? What are the stat's on the ports showing?

New Member

Re: stp ports leaving and joining bridge

lots of users are complaining. The status is the ports are joining and leaving the bridge. Error message = PAGP-5-PORTFROMSTP, I reviewed the error message from Cisco and they basicly said contact TAC. Do you think it a software bug. I currently running version 5.5(11a).


Re: stp ports leaving and joining bridge

If the users are complaining then I would look at speed /duplex mismatches for the ports , this will cause what you are seeing . If you auto on the switch then the users NIC's "must" be set as auto . if you hardcode the ports then the users nics must be hardcoded to match . Also look for high numbers of alignments and crc errors , this will also indicate a mismatch .

Cisco Employee

Re: stp ports leaving and joining bridge

The following page discusses the common causes for these messages.

Also what software version are you running on the 4006? 6.3(10) should be a good code to run as it has lot of bug fixes