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Solved: How do I fix MAC Address not detected over VPN?


This article describes the behavior where a MAC Address is not detected when a client connects over managed VPN.

This can occur when Agent information is either not received or not processed.


FortiAC version 8.x, and 9.x.


Step 1: Ensure the agent traffic is reaching the appliance.

Step 2: If agent the traffic is reaching the appliance, enable debug for Agent communication. In appliance CLI type:

nacdebug –name PersistentAgent true <----- If using Persistent Agent.
nacdebug –name AgentServer true <----- If using Dissolvable Agent.
tail -F /bsc/logs/output.nessus

Step 3: Have client connect.

Step 4: Type Ctrl-C to stop tail.

Step 5: Disable debug:

nacdebug –name PersistentAgent false
nacdebug –name AgentServer false

Step 6: In /bsc/logs/output.nessus output, look for ‘PAConnectionStatus’. There should be messages for the MAC address for the remote user.

Alex Lim is a certified IT Technical Support Architect with over 15 years of experience in designing, implementing, and troubleshooting complex IT systems and networks. He has worked for leading IT companies, such as Microsoft, IBM, and Cisco, providing technical support and solutions to clients across various industries and sectors. Alex has a bachelor’s degree in computer science from the National University of Singapore and a master’s degree in information security from the Massachusetts Institute of Technology. He is also the author of several best-selling books on IT technical support, such as The IT Technical Support Handbook and Troubleshooting IT Systems and Networks. Alex lives in Bandar, Johore, Malaysia with his wife and two chilrdren. You can reach him at [email protected] or follow him on Website | Twitter | Facebook

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