[c-nsp] STP root on CAT6513 with CatOS

[Peter Rathlev]

On Thu, 2007-11-22 at 19:49 -0300, luiz.maia at light.com.br wrote:
> I plan to change the STP root to CAT6513 using the command set spantree
>  root. I´d like to ask:
> 
> 1. Is this command enough?

The "set spantree root" set the bridge priority to 8192. If your current
root bridge has a lower priority it will not be enough. Use the "set
spantree priority <priority> <VLAN list>" instead.

> 2. How this change can affect the LAN availability?

Your network will hopefully elect the new root switch and thus run
through the usual STP phases. If you use regular PVST+ this means about
50 seconds of pause.

> 3. Is it necessary to use the STP root guard if I have LAN control?

The root guard feature makes sure a new root will not be elected from
the specified port. If another bridge connected to that port tries to
become root, the port changes to root-inconsistent state and stops
forwarding traffic.

I'm not sure what you mean by LAN control. If you mean that you are the
only one adding devices to your LAN, that root guard might not be
necessary. If you have trunks facing out of your network, root guard
could be a good idea on these ports.

Hope this helps. :-)

Regards,
Peter Rathlev