You need to put a sniffer on those ports to discover the destination for the unicast flooding.
-- Eric Cables On Mon, Aug 17, 2009 at 6:01 AM, C and C Dominte <[email protected]>wrote: > Hi, > > I am still experiencing unknown unicast flooding with the Catalyst 6509 VSS > 1440 configuration. > > I have tried two more tests, to check if the flood will stop: > > 1. I turned off the routed-mac feature > > #sh mac-addr aging-type routed > Routed MAC aging : disabled > > 2. I configured the arp timeout for each VLAN interface to 900 seconds > > To test if this solved the problem, I enabled 4 interfaces on Switch 2, and > as soon as that was done, 100 mbps flood of unknon unicast was sent to all > trunk ports. > > I pasted below the MAC address aging time that is currently 3 times the > syncronisation time: > > Syncronisation time: > > Global Status: > Status of feature enabled on the switch : on > Default activity time : 160 > Configured current activity time : 640 > > Mac address aging: > > #sh mac-addr aging-time > Vlan Aging Time > ---- ---------- > Global 1920 > no vlan age other than global age configured > > I am really out of ideas as to what can cause this loop, that then > generates the unknown unicast flood. Has anyone experienced anything similar > and can offer any advice on why this is happening? > > Thank you > > Catalin > > --- On *Fri, 7/8/09, Eric Cables <[email protected]>* wrote: > > > From: Eric Cables <[email protected]> > Subject: Re: [c-nsp] VSS 1440 issues > To: "Kevin Loch" <[email protected]> > Cc: "[email protected]" <[email protected]> > Date: Friday, 7 August, 2009, 8:43 AM > > > Agreed, your mileage may vary on the exact timers to use (I ended up at 900 > seconds), but synchronizing MAC and ARP aging timers should solve your > unicast flooding issues, assuming the traffic is to legitimate > destinations. > > Have you captured any traffic to identify the destination of flooded > traffic? > > -- Eric Cables > > > On Thu, Aug 6, 2009 at 9:35 PM, Kevin Loch > <[email protected]<http://mc/[email protected]>> > wrote: > > > C and C Dominte wrote: > > > > Thank you for your advice, however, increasing the timers > >> did not work. > >> > >> > >> I powered down the active linecards from switch 2 > >> yesterday to see if it stopped the unicast flood, which it did. > >> > >> Today I increased the mac address syncronisation activity > >> time to 640 and the mac address aging time to 1920 (3x640) as below: > >> > > > > While I have not run 6500's in VSS mode I have run into similar unicast > > flooding with certain non-VSS configurations of 6500's. The most > > reliable fix I have found is "arp timeout 120" in the affected vlan > > interfaces. > > > > - Kevin > > > > _______________________________________________ > > cisco-nsp mailing list > > [email protected]<http://mc/[email protected]> > > https://puck.nether.net/mailman/listinfo/cisco-nsp > > archive at http://puck.nether.net/pipermail/cisco-nsp/ > > > _______________________________________________ > cisco-nsp mailing list > [email protected]<http://mc/[email protected]> > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ > > > _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
