PPPOE users under NE40 cannot access network with old net card. Change a new net card, users can be online.
Change problematic port on NE40 and the problem is solved.
Four ports between NE40 and MA5200 are enabled port aggregation and VLAN transparent transmission. After aggregation, NE40 makes HASH computation according to source MAC and destination MAC and decides which link the traffic passes. The source MAC address is different, the link that the traffic passes is different.
One aggregation port on NE40 or MA5200 is problematic, but the interface is still up. Aggregation port cannot auto switch and old net card traffic still passes this problematic port, so the packet with old net card still passes this problematic port and old net card cannot ping through the gateway. Change net card. MAC address changes and HASH computation HASH another normal link, so it can access network.