No Spanning-Tree Vlan

[fing8733]

We are in the process of cleaning up our vlans on our access switches.  Currently we use VTP to propigate all of our vlans to the devices.  We would like to change these over to transparent and then just add them as we need to.  In all honesty we do not need all that many vlans on the access switches.  I would like to know if spanning-tree is in use on our core will it be effected by any of the access switches that are only connected with a single link?

My plan is to do this:

1) Change the VTP mode from client to transparent

2) remove any vlans that are not being used currenlty on the switch

3) issue the command spanning tree vlan 1 - 1000

4) configure allowed vlans on the trunk so we do not allow all that traffic to the access switch

If we have something like the following

----------------->Core Switch--------------->Access Switch

Will spanning tree be effected on the left side (down stream) of the Core switch if I am only doing the no spanning tree command on the Access Switch?  I would like to make sure that it will not make spanning tree reconverge on the core links.

Thanks!

[cadet alain]

Hi,

if the vlans don't exist then there ain't no spanning-tree instance for them anymore.

I highly recommend you not to do no spanning-tree command on the switch because if one day you have a redundant link and you forgot you disabled spanning-tree you'll get a loop.

Regards.

Alain

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[fing8733]

The vlans would still exist on the Core switch and downstream from that.  It would just not exist on that access switch unless we wanted to add it later for use.  I would not be using the "No Spanning-Tree" command that is just want it says on the switch right now becuase we are over the vlan limit for the model switch we have.

[Alessio Andreoli]

Hi Robert,

I think you have a correct understanding of your VTP migration. Nevertheless, I would like to underline two things

1) consider the possibility not to issue the command at point three(stp default settings work well)

2) as final stage, do not miss to migrate the VTP server too. Your core network needs to own the same logic than the rest of your layer 2 network to be stable

Ps: just as curiosity, check the VTP v3. There are quite a lot of interesting solutions even if I would prefer transparent mode myself

Hth

Alessio

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