[c-nsp] Weird problem with 2960S and desktop switch

[Peter Rathlev]

On Wed, 2014-01-08 at 09:37 +0100, Garry wrote:
> After shut/no shut, the port again went down due to BPDU.
> Disabling BPDU guard caused the whole switch to lock up while the
> desktop switch was connected, even though checking the logs after
> removing the desktop switch (and a bit of additional waiting time, in
> which I assume spanning tree came back up) did not show any errors or
> messages between the int up and down of that port.

Are you saying you had a loop (when BPDU Guard was disabled) or not?

If you had a loop (confirmed by observing e.g. fully utilized links
everywhere) even though the physical setup doesn't seem to contain loops
you might have a malfunctioning switch among your devices.

Otherwise it sound like BPDU Guard just does what you have asked it
to. :-)

If you don't have "spanning-tree bpduguard enable" configured on the
interface it might be enabled via the global "spanning-tree portfast
bpduguard default" command. In that case you can disable it for a single
interface with "spanning-tree bpduguard disable".

-- 
Peter