Why DHCP users go online through the S2700, but cannot access the Internet

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When a large number of DHCP users go online through the S2700, the S2700 generates a large number of dynamic DHCP snooping binding entries. On the S2700 V1R6C00SPC800, the software provides incorrect priority settings for DHCP snooping binding entries and IP source guard and DAI ACL rules, and the ACL rules have a higher priority than DHCP snooping binding entries. As a result, the software delivers the ACL rules but not DHCP snooping binding entries. User packets cannot be forwarded because no binding entry is available.

Solution: Install S2700SPH006, enable DHCP users to go online again, and reconfigure IP source guard and DAI on the physical interface from which DHCP users go online.

Other related questions:
PPPoE configuration on S series switch
PPP over Ethernet (PPPoE) provides point-to-point connections over the Ethernet, so that multiple hosts can be connected to the Internet through the same access device and users can implement access control and accounting for these hosts. For the detailed PPPoE configuration, see Example for Configuring the Device as a PPPoE Server to Allow PPPoE Users on Campus Network to Access the Internet in the S7700&S9700&S12700 Series Switches Product Documentation.

Why cannot an AP go online when the AR functions as an AC
#NAME?

The speed of Internet access through PPPoE dialup is slow
The MTU of the PPPoE dialer interface is 1492 bytes. When the length of Layer 3 packets sent from this interface is larger than the MTU and non-fragmentation is configured, packets cannot be sent out and the Internet access speed is low. You can run the tcp adjust-mss value command on the dialer interface to modify the MSS (Max Segment Size) during TCP negotiation so that the packet length is shorter than the MTU of the dialer interface. Then packets can be properly processed and Internet access is smooth.
For example, change the MSS of the dialer interface to 1200.
<Huawei> system-view
[Huawei] interface dialer 0
[Huawei-Dialer0] tcp adjust-mss 1200

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