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Static route protocol is enabled among four devices. Add static backhaul route on two NE80Es and default route on 8850. And then OSPF is enabled among four devices. Import direct and static route on 8850 and cancel static backhaul route on NE80E.
After configuring OSPF, parts of users can obtain address, but they cannot open webpages. QQ sometimes can be used, sometimes it cannot. 8850 and NE80E have no abnormal alarm.
Delete false static blackhole route on 8850A and the network recovers.
The segment address is distributed on 8850A and then on 8850B. But the segment address is deleted only on 8850A and static balckhole route is not deleted. Before the whole network enables static route, other devices cannot perceive the balckhole route and there is no such problem. After OSPF is enabled, the blackhole route exists in the whole network and results in the problem.
Users can authenticate and 8850 has no abnormal informaiton; NE80E attached LAN users can access network. The device is not problematic.
Before the network is abnormal, the route is adjusted. Routing problem conduces users to be online abnormally.
Check user information on 8850 and problematic users are in one C-type address.
Check the rotue of corresponding address on NE80E. There are two next-hop from NE80E to one C-type address and they point to two 8850.
Check address pool on 8850. The C-type address only distributes it on 8850B. 8850A does not distribute the segment address, but 8850A has one static route to blackhole. Import direct and static route in OSPF of 8850. If users on 8850B obtain the address, NE80E defaults load balance. Half traffic can returns to users and other traffic is discarded in blackhole on 8850A.