[c-nsp] Divide large PVST domain?

[Federico Cossu]

If you are looking for real fun, aggregate redundant links with
etherchannel, then disable STP.
Il 09/lug/2014 18:21 "Victor Sudakov" <vas at mpeks.tomsk.su> ha scritto:

> John Gaffney wrote:
> > You could consider MST to reduce the number of STP instances.
> > Sometimes that can increase efficiency.
>
> Am I correct to assume that every time I need to move a vlan from one
> MST instance to another, my whole MST domain will fall apart until the
> MST reconfiguration is complete on all the switches?
>
> Somehow I don't like this idea.
>
>
> > However what you are probably looking for is "spanning-tree
> > diameter" command. If I recall that can make some auto adjustments
> > to STP timers to accommodate for large switched networks.
>
> Even with the timer adjustments the maximum diameter is about 18
> devices. Still my train does miraculously work provided the root
> switch is in the middle.
>
>
> > You should also be aware that 20 switches connected in a straight
> > line (hence middle switch) gives you a single point of failure.
>
> It is not exactly so because the radio equipment has a way to shunt
> the failed switch. So the continuity of the train can be quickly
> restored. But it is a different topic.
>
> I also have a backup root close to the middle of the train.
>
> This is also the reason why going all L3 is not an option. You cannot
> simply shunt a router.
>
> > If it is truly a "train" of switches you could also not run STP - no
> > ring/redundant link = no loop.
>
> As I have already said before, 'I have a "train" topology with some
> redundant links between neighboring switches'.
>
> There are however no rings in the sense that redundant links are only
> between neighbors.
>
>
> --
> Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
> sip:sudakov at sibptus.tomsk.ru
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
>