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Cisco Bug: CSCvv48770 - C1000 Stack - Broadcast packet looped back on downlink port causing MAC Flap.

Last Modified

Oct 04, 2020

Products (1)

  • Cisco Catalyst 1000 Series Switches

Known Affected Releases


Description (partial)

On Cat1K Hstack setup, broadcast traffic entering member port  is looped back on downlink port 0. This is causing MAC flap on Cat1k and also cause some incorrect traffic forwarding to connected devices.

-- Seen only with hstack setup.
-- MAC flap is seen only with downlink port (Port 0 of the same asic to which that uplink port belong to). Asic/port combination can be seen using 'show platform pm if-numbers' command.
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