[c-nsp] Rapid Per-VLAN Spanning Tree and Third Party

[Phil Mayers]

On 27/10/10 08:25, Phil Mayers wrote:
> On 10/27/2010 07:56 AM, Robert Hass wrote:
>> Hi
>> Is any other vendor than Cisco (eg. Force10, Brocade/Foundry, Extreme)
>> supports Rapid Per-VLAN Spanning Tree on their switches ?
>
> Yes. We use both Extreme and Foundry in Rapid-PVST mode, interacting
> with Ciscos.

A couple of people have asked what config we use on Extreme/XOS. Assume 
an existing vlan "USERS" w/ tag 138, tagged[1] on ports 1:48 and 2:48:

create vlan USERS
conf USERS tag 138
conf USERS add port 1:48,2:48 tagged

...then to add PVST we do:

create stpd s138
configure stpd s138 mode dot1w
configure stpd s138 default-encapsulation pvst-plus
configure stpd s138 add vlan USERS ports 1:48,2:48 pvst-plus
configure stpd s138 tag 138
enable stpd s138

...in future when adding ports to vlan, you must use the following form 
of the command to both tag & STP enable at the same time:

conf USERS add port 3:48 tagged stpd s138

...else you'll create a loop. Obviously if the neighbouring switch is 
not participating in STP and has no loops, you could omit this but I 
tend not to for consistency with Cisco.

I believe the older ExtremeWare platform can also do this, but the 
syntax is different. The Extreme STP stuff is a bit complex, so read the 
docs is your best best.



[1] Note: XOS requires a vlan to be tagged to do PVST; you cannot have 
an untagged/native vlan doing PVST; we run with:

vlan dot1q tag native

...on our ciscos anyway[2], but bear this in mind.

[2] Except where the platform doesn't support it, in which case we use a 
dummy native vlan. Yay IOS consistency :o(