[c-nsp] Migration to Rapid-PVST

[Robert Hass]

On Sat, 13 May 2006, Per Carlson wrote:

>If you are going to change the STP, why not take the full step to to
>MST? When using "desktop switches" in the network, you will sooner or
>later run into the STP instances limitation (128 instances). By
>running MST, this will no longer be an issue.

Thanks for the tip. It could be very good idea for future - as we're
adding 3-10 VLANs each month.

Basing on my first post with network diagram how many instances you
recommend to have ? And which switches should be root-bridges for these
instances.

>- how the edge ports (customer ports) are configured (are those
>  running STP or not)

We have configured bpdu-filter and SPT portfast at customers ports.
Most of customers using static routing, so We're terminating them on
both our 7304 routers providing redundancy with HSRP.

>- the number of MAC-addresses that needs to be flooded and
>  relearned

Most of VLANs carring up to 2-6 MACs. I worst case it will be 50 VLANs
* 6 MACs = 300 MACs.

>Be aware that there are two different MST implementations in IOS,
>one pre-standard and one standard. As far as I have seen, those
>will interoperate without any problems. But running the same type
>in the whole network is probably a Good Thing (tm).

I have 12.2(25)SED and 12.2(25)SEE on 3550/3560/3750 and 12.1(22)EA7 on
2950. Is MST implementation in 12.1(22)EA7 is same that in
12.2(25)SE{D/E} ?

Robert