MA5200F is attaches with DSLAM, and establishes a C-class network (192.168.0.0/24) for intranet of a company. 192.168.0.1 serves as server and the other addresses as clients. Earlier, the clients could access the server normally, but because of the capacity expansion, some clients attached cannot access the server then once MA5200F is replaced with MA5200G. The intranet of the company crashes.
1. The configurations of MA5200G are correct in checkup.
2. The clients could ping to the shared gateway address (192.168.0.1), indicating that the link from L2 network to MA5200G is normal.
3. Check the information why the clients under MA5200G cannot access the server, and it is found that those clients and the server are connected to MA5200G through the same one DSLAM; the clients connected through other else DSLAM could access the server well. Through checkup, MA5300 serves as DSLAM, using SMART VLAN. In other words, the ports of accessed users are isolated through L2 VLAN, but all users from MA5300 to MA5200G belong to the same VLAN.
4. Enable the ARP proxy of the port of MA5200G for BAS, and the problem is solved. The command is:
The ARP proxy for different ports or different VLANs of MA5200F are enabled, and that for the same port and the same VLAN is also enabled by default. For MA5200G, the ARP proxy for different ports or VLANs are also enabled, but that for the same port and VLAN is disabled by default. Therefore, once MA5200F is replaced with MA5200G, and the port receives the ARP request from the client, the packet is discarded. This is because the server and client connected to the same DSLAM equipment are in the same network segment, but all users are at the same port and the same VLAN; moreover, the ARP proxy in the same port and VLAN is disabled by default. At the time, the client host cannot communicate with the server at L2 because of L2 isolation for access ports at DSLAM. This is why the problem occurs.