When some Eth-Trunk member interfaces go Up or Down, the path cost of the Eth-Trunk will change. STP recalculates the path cost, causing the network topology change. Then STP recalculates the spanning tree, resulting in network flapping.
Run the stp [ process process-id ] [ instance instance-id ] cost cost command in the Eth-Trunk interface view to set the path cost of the Eth-Trunk to a fixed value. Then member interface change does not affect the path cost of the Eth-Trunk, and the network topology is not affected.
<HUAWEI> system-view [~HUAWEI] interface eth-trunk 1 [*HUAWEI-Eth-Trunk1] stp cost 200 [*HUAWEI-Eth-Trunk1] commit