Terminal authentication failed after AC roaming

Null

Terminal first connects to vendor A's AC, obtains IP address a, and can access the Internet normally; after roaming from vendor A to H3C wireless AC device, it cannot access the Internet normally.

1. The terminal initially connects to the A vendor's device, successfully obtains address a, and can also be authenticated through the A vendor's server, and can access the internet normally.

2. When roaming from the A vendor to our company's device, the terminal has already obtained a new address b, but the IMC server still sees the representation of the terminal authentication as belonging to address a, causing the network to be inaccessible.

3. Analyzing the principle, the terminal IP on the IMC is carried by the AC through the billing message. Here, the terminal has already obtained a new address b through DHCP, so why is the AC still carrying the old address? The AC learns the terminal's IP address through two methods, one is the DHCP message, and the other is the ARP message. Before the terminal obtains a new address through DHCP, it may use the old address to send ARP messages, and the AC will recognize and learn the terminal's address from this old ARP message. As a result, the AC uses the old terminal IP address to send billing messages.

Turn off the feature of learning terminal IP on AC through ARP, and only retain the feature of learning terminal IP address through DHCP.

undo client ipv4-snooping arp-learning enable