[c-nsp] Re: need help on switch configuration (Arturo Servin)

[Elmar K. Bins]

aservin at remoteconfig.net (Arturo Servin) wrote:

>     In this case it won´t. One trunk only carries vlan 100 and the other 
> only carries the vlan 101 (I do not know why they are using trunks to 
> carrie just one vlan, but, I was not the original person who post the 
> problem).

The reason why people configure trunks is that it's recommended in
all Cisco literature ;-)

The above (two trunks carrying different VLANs) will only work if
your spanning-tree mode is set to pvst; as I can see from the cited
block, this is the case.

If it was my box, I would now configure an explicit _native_ VLAN
on the trunks (like "switchport trunk native vlan 999"), and then
disable spanning-tree for that vlan (like "no spanning-tree vlan 999").

Elmar.

PS: The obvious easy way, of course, is to dismiss the trunks and
    run the interconnection as access ports.