Huawei server E9000 is the blade server, does not have the stardard network interface such as RJ45 or Fibre channel.Its’ network adapters are connecting with the different kind of switch pannels.E9000 chassis is design to fix four switch pannel ,which corresponding to the four lanes of pcie bus. The switch pannel CX311 is show as below.
For example ,LOM X722 passthrough two network adapter interface,we defined them as LOM#1,LOM#2.The LOM#1 will connect with 2X switch pannel and the X722#2 will connect with 3X switch pannel, so LOM#1 and LOM#2 does not have network message passing.Even plugged the network cable into 2X switch pannel and 3X switch pannel, the network message passing between 2X and 3X is not stable.I considerthis problem may be caused by its design architecture .And what’s more, it also caused the failure of IOMMU test and I have to spend too much time for solving this problem.
Refers to the above capture of network archtectture, DUT meas NIC.
The IOMMU test is for testing the message passing between DUT3 and DUT1,between DUT3 and DUT2.However the network performance of DUT2 is so bad during the test ，since the DUT2 is not in same switch pannel with DUT1&DUT3.
The solution is to add an network adapter DUT4 on the ESXI AUX host ,so that DUT4 and DUT2 will be connected to the same switch pannel.The IOMMU test does not ask for DUT4, so the test will not set DUT4 into the vswitch in the ESXI web client,we have to add DUT4 as the second uplink adapter of AUX vswitch by mannul.
When completed the above configuration,DUT3 and DUT4 will conbine into an adapter with pass-through mode, the RX performance of DUT2 will become normal. All of IOMMU test passed.