I have a theory about why it didn't work on your device. Its what I expected would happen and why I didn't suggest what Russell did to just loop one LAN port to another. I think its due to the architecture.
What make and model is your switch/router? On Thu, Dec 26, 2019, 2:24 PM <[email protected]> wrote: > It seems that in my case - looping LAN1 with LAN2 and sending/receiving > WAN<-->WLAN3 traffic leads to no visible traffic degradation. That > probably mean > that I failed to create lan loop. > > The lights were "kind of" busy on LAN1 <--> LAN2, but the wlan3 and > upstream WAN > are slow enough to observe any effect on that traffic. > > I will try to gather together 8+ switches when I get home after the New > Year. > With that I may be able to observe some traffic pattern change when > crossing > switching depth 7. > > > The router/switch looks this way: > > - WAN (eth0) > > +- LAN1 (eth1) > > +- LAN2 (eth2) > > +- WLAN3 (wlan0) > > The router is running openWrt. > > > > Tomas > > On Wed, 2019-12-25 at 09:15 -0800, Mike C. wrote: > > > > > > I happened to have a netgear FS105 nearby. Plugging in a laptop to a > switch > > > port, and plugging a patch cable between two other switch ports and > pinging > > > a random ip address from the laptop set off the broadcast storm. > Running > > > tcpdump from the laptop showed a bunch of "MPCP, Opcode Pause, length > 46" > > > packets. Unplugging the loop, the packets stop immediately. > > > > > > > The reason this works and why I suspect it won't work on the OPs router > is > > the Netgear isn't a 802.1D (Spanning Tree Compliant) switch. Those > > multicast packets are flow control packets and would not be forwarded out > > all switch ports downstream as per 802.1D they're reserved to be acted > upon > > only by the switch. > > _______________________________________________ > > PLUG mailing list > > [email protected] > > http://lists.pdxlinux.org/mailman/listinfo/plug > _______________________________________________ > PLUG mailing list > [email protected] > http://lists.pdxlinux.org/mailman/listinfo/plug > _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
