6 Replies Latest reply on Sep 24, 2013 1:40 PM by Patrick_Kutch

    The problem of VLAN and Ping when using the SR-IOV function of 82599

    yixiuge101

      When I use the SR-IOV function of 82599, I allocated a VF to a VM under the XEN monitor in the host, and I have the following questions:

      1. Can the VM receive the frame with the VLAN tag head?
      2. Can the SR-IOV function of 82599 support FCoE( Fibre Channel over Ethernet)?
      3. I use Brocade VDX 6730 to replace Brocade 8000 as the switch  which is directly connected to the host.When the dcb state is on and in the mean time the sr-iov function of 82599 is used,the ixgbe driver has error messages as belows:

      ixgbe 0000:84:00.0: eth2: NIC Link is Up 10 Gbps, Flow Control: RX/TX

      ixgbe 0000:84:00.0: eth2: detected SFP+: 5

      ixgbe 0000:84:00.0: eth2: NIC Link is Up 10 Gbps, Flow Control: None

      ixgbe 0000:84:00.0: eth2: detected SFP+: 5

      ixgbe 0000:84:00.0: eth2: NIC Link is Up 10 Gbps, Flow Control: RX/TX

      ixgbe 0000:84:00.0: eth2: detected SFP+: 5

      ixgbe 0000:84:00.0: eth2: NIC Link is Up 10 Gbps, Flow Control: None

      ixgbe 0000:84:00.0: eth2: detected SFP+: 5

      and it repeated again and again. In addition, the host with the 82599 NIC can not ping other hosts. But everything turns normal without the SR-IOV function.

      I’m very confused with all the problems and I desired to know how to resolve them.

        • 1. Re: The problem of VLAN and Ping when using the SR-IOV function of 82599
          Patrick_Kutch

          Wierd - I know I replied to this a week or two ago, but now is showing up as a new thread.  Gremlins must be about.

           

          In general, unless you are creating your own packets and inserting VLAN tags, the VLANs are stripped by the time they reach the VM - by design.  Usually the VM should not know it is assigned to a VLAN.

           

          The VF on the 82599 does not support FCoE.

           

          I've not seen the error you are showing.  Are you trying to do SR-IOV on some VF's and do FCoE to the PF?  Do you have the latest drivers?

           

          thanx,

           

          Patrick

          1 of 1 people found this helpful
          • 2. Re: The problem of VLAN and Ping when using the SR-IOV function of 82599
            yixiuge101

            Patrick,

            Thank you for the reply.

             

            Yes,i have the latest drivers.When dcb is off,then the PF can "ping" other hosts in the sr-iov virtualization environment,but when dcb is switched on,those error messages show.

            • 3. Re: The problem of VLAN and Ping when using the SR-IOV function of 82599
              wuyunxiang

              you said “The VF on the 82599 does not support FCoE.”,why?In my opinion,if you can use VF on 82599,you can use ethernet by VF on 82599.And fcoe just need ethernet for send or receive.
              another question:The PF on the 82599 does not support FCoE?
              addition:ixgbe version 17.4 release note

                   adds the following features (October 17, 2012)

                         support-SR-IOV & DCB coexist on 82599

               

              thanx,

              wuyunxiang

              • 4. Re: The problem of VLAN and Ping when using the SR-IOV function of 82599
                Patrick_Kutch

                A VF is a 'lightweight' PCIe function. It does not have all the same capabilities as a PF.  Features such as FCoE, VMDq,SR-IOV, etc. all take hardware resources.  SR-IOV is supported by the Intel 82599 PF, but not a VF.

                 

                You may also run SR-IOV and DCB concurrently, however DCB (and therefore FCoE) is limited to the PF.  This means you can run FCoE on the PF and still have standard Ethernet capability on your VF's.

                 

                Hope this clears things up.

                 

                - Patrick

                • 5. Re: The problem of VLAN and Ping when using the SR-IOV function of 82599
                  wuyunxiang

                  i very apprecite it  for your reply!And still have something not understand.


                  you said "A VF is a 'lightweight' PCIe function. It does not have all the same capabilities as a PF.  Features such as FCoE, VMDq,SR-IOV, etc. all take hardware resources."

                       The FCoE,in your word,it means the FCoE offload capability?

                      


                  "You may also run SR-IOV and DCB concurrently, however DCB (and therefore FCoE) is limited to the PF."

                       you mean DCB are the features of layer 2 for  only PF(not include VFs)?

                   

                  "This means you can run FCoE on the PF and still have standard Ethernet capability on your VF's."

                       you mean VFs have standard Ethernet capability,not include any about FCoE offload capability?i see FCoE frame as a Ethernet Frame,so can I use the standard Ethernet capability to send/receive FCoE frame?

                   

                  Waiting for your response。

                   

                  thanks,

                  wuyunxiang

                  • 6. Re: The problem of VLAN and Ping when using the SR-IOV function of 82599
                    Patrick_Kutch

                    FCoE uses DCB, for which we have hardware assists that work in conjunction with the CPU and FCoE network stack.

                     

                    You could theoretically run FCoE on a VF with a purely sofware FCoE stack.  Would have a pretty high CPU overhead and less performance, but it would work.  I believe our FCoE solution though is designed to use hardware assists in the device.

                     

                    The PF is a full featured (lots of cool stuff) function, the VF was designed to basically send and receive Ethernet packets with little in the way of hardware assists (does VLAN tagging and maybe a few other things).

                     

                    While I can't say for certain, it would be a good bet to assume that future Intel Ethernet devices will support more robust VF's with features such as FCoE.  However as I mentioned, that is not something I can confirm or deny.

                     

                    Hope this helps.

                     

                    - Patrick