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Cisco Bug: CSCta61825 - Blocking of unknown multicast flooding breaks ARP resolution

Last Modified

Feb 15, 2018

Products (1)

  • Cisco Catalyst 4000 Series Switches

Known Affected Releases


Description (partial)

When "switchport block multicast" is configured on a port (to block unknown multicast traffic), the ARP resolution for the hosts connected to that port is broken and broadcast traffic is blocked.

All broadcast traffic such as ARP request and DHCP discovery are not received by the port.

When "switchport block multicast" is configured on a port.
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