HI,
When encountering latency/ traffic issue, suggest to do packet captures on the ingress/egress port to see if the latency/packet loss happened on the ACI fabric.
If yes and you know the exact IP address, use Visibility & Troubleshooting tools to check the detailed info on where it could be lost or get delayed.
Check counters under port if there are any drops. (crc, output discard,etc)
Check if there're any error happened related to issue BD.
If issue persist, suggest to open TAC case for further troubleshooting.
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You can also learn more about Cisco ACI through our live Ask the Experts (ATXs) session. Check out the ATXs Resources [https://community.cisco.com/t5/data-center-and-cloud-knowledge/cisco-aci-ask-the-experts-resources/ta-p/4394491] to view the latest schedule for upcoming sessions, as well as the useful references, e.g. online guides, FAQs.
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