Hi Have you configured loop protection? https://www.juniper.net/documentation/en_US/junos/topics/example/stp-loop-protection-qfx-series.html
On a design note, why not use Virtual Chassis instead? /Roger On Mon, Jul 10, 2017 at 6:34 AM, Victor Sudakov <v...@mpeks.tomsk.su> wrote: > Dear Colleagues, > > There is a ring of EX4200 switches, please look at > http://noc.sibptus.ru/jun1.png > > If MUX1 fails, the MSTP topology adjusts and the PCs continue to see > one another just fine. > > However, some switches become inaccessible in the management vlan > (vlan3 in this example). For example, you can still ping 192.168.1.3 > from 192.168.1.2, but not 192.168.1.4 from 192.168.1.2. > > One important note. If MUX1 fails, the corresponding interfaces on > 192.168.1.2 and 192.168.1.4 don't go down, it is only the traffic > (including BPDUs) that stops flowing through the mux. > > If I shutdown the corresponding interfaces on 192.168.1.2 and > 192.168.1.4 (or use OAM to shutdown the interfaces automatically when > the mux fails), the problem disappears and I can ping any switch from > any switch. > > What's the theory behind this? > > "clear arp" and "clear ethernet-switching table" don't fix the > problem. > > -- > Victor Sudakov, VAS4-RIPE, VAS47-RIPN > AS43859 > _______________________________________________ > juniper-nsp mailing list juniper-nsp@puck.nether.net > https://puck.nether.net/mailman/listinfo/juniper-nsp _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp