Preview Tool

Cisco Bug: CSCvt18739 - Cat9K - incorrect source mac address used for L3 packets after L3 link flap

Last Modified

Oct 27, 2020

Products (1)

  • Cisco Catalyst 9300 Series Switches

Known Affected Releases


Description (partial)

After a L3 link flap, a cat9K device starts using an incorrect source mac address for L3 packets. The device has a combination of static macs (for anycast gateway functionality) and system mac.

This causes issues with end hosts that implement a fast path like behavior (they simply swap source/destination macs).

Combination of static mac and system mac in use.
Bug details contain sensitive information and therefore require a account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.