Troubleshooting approach for ACG1000 device online users with identical MAC addresses

Not involved

The MAC of online users on the ACG device is the same MAC. After configuring SNMP Layer 3 MAC address learning to synchronize users successfully, it remains the same MAC

1. To learn the real MAC address of the terminal, the ACG needs to enable SNMP on the Layer 3 device closest to the terminal (note: the terminal, not the ACG). Then, configure the SNMP cross-Layer 3 MAC address learning function on the ACG to learn the real MAC. The principle is that the ACG reads the ARP mib node of the Layer 3 device through the SNMP protocol and learns all ARPs of the Layer 3 device.

2. Click SNMP user synchronization on the ACG. If the synchronization is successful, it indicates that the SNMP configuration between the ACG and the Layer 3 device is correct.

3. If the MAC of the online user remains unchanged at this time, it indicates that the following part of the MAC address was filled incorrectly. The final source MAC of the corresponding user traffic received by ACG should be filled in (Note: deselect ip-mac binding; no binding is required)

Principle: ACG identifies the source MAC and source IP of a traffic flow. 1) Through the aforementioned cross-Layer 3 MAC address learning, it learns the MAC corresponding to the IP. 2) By identifying the MAC address in the screenshot below, ACG can replace it with the real MAC only if the source MAC of this traffic matches the MAC in the screenshot. In summary, the MAC below should generally be filled with the MAC address of the directly connected Layer 3 peer of ACG. This can be determined by capturing the source MAC in user traffic on ACG.

Refer to the analysis process and modify the configuration accordingly