If it is a trunk to a server - enable "portfast trunk" so it is unaffected by TCN's.
When you say you do not run spanning tree - what do you mean by that? You disabled it for certain VLAN's or the whole switch? -----Original Message----- From: cisco-nsp <cisco-nsp-boun...@puck.nether.net> On Behalf Of Garrett Skjelstad Sent: Monday, October 22, 2018 12:56 PM To: Mike <mike-cisconspl...@tiedyenetworks.com> Cc: cisco-nsp NSP <cisco-nsp@puck.nether.net> Subject: Re: [c-nsp] What causes mac table relearning? This message originates from outside of your organisation. Yes, TCN is where I would start, MST is famous for this as well. On Wed, Oct 17, 2018, 14:32 Mike <mike-cisconspl...@tiedyenetworks.com> wrote: > Hi, > > > I have a network consisting of 3560g switches and I do not run > spanning tree in this network. I have noticed a symptom when a vlan > trunk interface goes down/up, all mac addresses in the vlans carried > by that trunk also seem to be cleared at the same time. Im not just > talking the mac addresses on the port itself; rather, across the other > switches themselves , even for mac addresses that have no connection > to the port itself they just happen to be in one of the vlans. If I > have missed something fundamental I'd love to know but I am not aware > of any lan switching rules that would require this behavior. > > > Mike- > > _______________________________________________ > cisco-nsp mailing list cisco-nsp@puck.nether.net > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ > _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/