Ben Dale wrote: > > > > I have several EX4200 switches with redundant links, all are running > > MSTP with a couple of MSTIs. > > > > If I include an older switch which can only run old-fashioned STP, > > will they interoperate and still keep the topology loop-free? What if > > it can run STP and RSTP, but not MSTP? > > They will interoperate, however there are key differences to be aware of:
> - STP/RSTP forms topology with STP bridges regardless of whether > correct VLANs are trunked on ports - this can mean that topologies > may form that isolate VLAN segments if you haven't configured > trunked ports correctly on all links > - STP/RSTP bridges will treat an MSTP network (regardless of how > many switches it contains) as single contiguous bridge, so you may > find that the ports that block in your RSTP network aren't quite > where you expected them to be when simply counting the radius from > the root bridge. Ben, thank you for your explanation. > > > > > A link to some good documentation is also appreciated. > > > > TIA for any input. > > I highly recommend Petr Lapukhov's work here: > > http://blog.internetworkexpert.com/2010/02/22/understanding-mstp/ I remember reading it when I set up MSTP for the first time, but I skipped the multi-region part of if. And the legacy STP link should look to MSTP switches as a foreign region, from what I was told. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN sip:suda...@sibptus.tomsk.ru _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp