[c-nsp] Maximum spannig tree instances

[David Hughes]

On 15/07/2009, at 4:22 AM, Geoffrey Pendery wrote:

>> Will adding new VLANs to an MST instance disrupt traffic flow for  
>> other
>> VLANs in that MST instance?
>
> Yes.  We've verified this.
> A trunk port carrying only VLAN 30, or even an access port carrying
> only VLAN 30.
> VLAN 30 is in instance 2.  You go into config mode and add VLAN 50 to
> instance 2 (or remove it from instance 2)
> The port, be it access or trunk, goes to blocking, learning,  
> forwarding.

But MST implements Rapid-STP in each instance (except 0 naturally) so  
even if the config change did recalc the tree it'll be sub-second.   
Not that any STP recalc is a good thing but at least it'll be over and  
done with quickly.


David
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