[c-nsp] etherchannel problems

[Holemans Wim]

We just got bitten by a serious etherchannel problem : we have an 2 gig
etherchannel link between 2 campus.
Someone on the other end misconfigured an interface (typed 6/1 instead
of 1/6)  and had overwritten the allowed vlans on one of the interfaces.
As a result of this, the interface was thrown out of the bundle (at that
side only) BUT the interface stayed UP. On the other campus, both
interfaces 
stayed in the bundle with very big problems as a result : the 6500 at
that side considered both lines as valid and distributed the packets
over both interfaces, sending half of the traffic in 'space'. 

If the interface had gone down as a result of the unbundling, there
would have been no problem. We only use static channel settings, so not
etherchannel negotiations between switches. Can this be solved with
dynamic etherchannel bundling ? Or someone has another solution for this
problem ?

Wim Holemans
Networkservices University of Antwerp