topic Re: Mutiple Authentication on Interface Causing Mac-Flap in Network Access Control

Mutiple Authentication on Interface Causing Mac-Flap

Ryan10 — Wed, 28 Aug 2019 07:54:10 GMT

Hi Cisco Engineers,

Have you experience a multiple authentication on one interface but there's no hub/switch connected to it. Only once PC connected to the interface but many Mac Addresses trying to authenticate (using 802.1x). As I traced the Mac Addresses, they are legit PC but connected to the ports of the other switch. It seems like Mac Spoofing.

I have researched what cause the issue, and some forums tells it's about Wake On LAN or Wake Up Proxy. But as I checked. there's no Wake On LAN or Wake Up Proxy configured on PCs/SCCM.

Please see the screenshots. Thank you.

Re: Mutiple Authentication on Interface Causing Mac-Flap

crathnaswamy — Mon, 27 Jan 2025 16:16:15 GMT

I have the same issue in 2024/25 after implementing NAC. ISE performing NAC on user ports, cauing MAC flapping. Any resolution or guidelines?

Re: Mutiple Authentication on Interface Causing Mac-Flap

MHM Cisco World — Mon, 27 Jan 2025 16:27:20 GMT

Please make new post

Thanks alot

MHM