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Cisco Bug: CSCvs50966 - Source class is 0 for return traffic

Last Modified

Oct 29, 2020

Products (1)

  • Cisco Nexus 9000 Series Switches

Known Affected Releases


Description (partial)

The sclass of an endpoint (MAC/IP address) is programmed with 0, thereby causing traffic to drop.

This is a timing scenario and user could run into this when an existing IP address is learned with a new MAC address on an another leaf node (L2R move). In this scenario, the existing IP address, which is a bounce on the original leaf node, can program the endpoint (MAC/IP address) with sclass 0.

VPC node
VPC1: Local MAC1/IP1 
VPC2: On-peer MAC1/IP1

Now, if IP1 is learned with MAC2 on a remote leaf node, MAC/IP1 can be programmed with sclass 0 on the VPC1/VPC2 nodes.
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