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    [solved] pfSense (2.6.0 & 22.01 ) is very slow on Hyper-V

    Scheduled Pinned Locked Moved Virtualization
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    • stephenw10S
      stephenw10 Netgate Administrator
      last edited by

      Yup, that probably would. There is clearly something else at work here though and it appears to be beyond just the NIC/driver.

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      • R
        RMH 0
        last edited by

        I have same issue as covered here:

        Win 2019 Server running Hyper-V

        All Ok on 2.5.2 moved to 2.6 and network speed dropped from, 500mb to 2.5mb. I did all the changes suggested here with VMQ etc. Also swapped WAN interface from Intel Pro 1000 PT Dual NIC to onboard Marvell Yukon 88E8059 and no difference.

        What did weirdly make a massive difference was using a VPN on my PC, I started NordVPN and my speed jumped back to 488mb. Strange thing was in pfsense it showed my WAN speed as 60mb. Dropping the VPN and speed dropped back bown to a couple of MB.

        Essentially the connection via pfsesne 2.6 runs at normal speed if your client is conencting through it on a VPN. All be pfsense thinks it is running at nearly 10x a slower speed.

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        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          TCP vs UDP maybe? Some hardware off-loading happening?

          Do you see error in the interfaces when it's slow?

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          • D
            Dominixise @stephenw10
            last edited by

            @stephenw10

            Hi Steve I can setup a zoom session with you on my server unless that requires paid tech support from netgate?

            Dom

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            • stephenw10S
              stephenw10 Netgate Administrator
              last edited by

              I'm not the guy for that, I know next to nothing about hyper-v. 😉

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              • D
                Dominixise @stephenw10
                last edited by

                packetcapture.zip @stephenw10

                Could be a Microsoft error too, I remember just after Christmas there was an windows update that cause some Hyper-V errors and maybe some are still present. My Server is up to date.

                But heres a packet capture of a speed testpacketcapture.zip

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                  Dominixise @Dominixise
                  last edited by

                  @dominixise
                  Also pftop while doing a speed testdom pfsense pftop.jpg

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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    No actual speedtesting shown there, was it filtered?

                    All small packets, some MTU issue?

                    Steve

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                    • D
                      Dominixise @stephenw10
                      last edited by

                      @stephenw10
                      Sorry i am new to getting logs, try this onepacketcapture (1).zip

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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Nearly! 😉

                        You probably want to filter by the client IP you are running the test on, if you're capturing on LAN. And set the capture to, say, 5000 packets.

                        Steve

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                          Dominixise @stephenw10
                          last edited by

                          @stephenw10

                          Okay thanks for the acknowledgment here is the new capture, I had to put the download on my webserver for download since its 5MB

                          https://zebrita.publicvm.com/files/packetcapture(2).cap

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                          • D
                            Dominixise @Dominixise
                            last edited by

                            @dominixise
                            Here is another one with just my host ip

                            https://zebrita.publicvm.com/files/packetcapture(3).cap

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                            • R
                              RMH 0
                              last edited by

                              A bit of digging and it looks like 2 issues to me.

                              One in Hyper-V which I have now got resolved, fix below (well for me anyhow)
                              One in pfsense that is missreporting throughput (I can live with that till a fix comes)

                              For Hyper-V I found this article on RSC https://www.doitfixit.com/blog/2020/01/15/slow-network-speed-with-hyper-v-virtual-machines-on-windows-server-server-2019/
                              Once I disabled RSC on all virtual switches my speed was back to normal. No restart needed, just go on to Hyper-V host, open powershell and input commands to disable RSC on each virtual switch.

                              These are commands I used

                              Get-VMSwitch -Name LAN | Select-Object RSC
                              Checks status, if true run next command LAN is my vswitch name

                              Set-VMSwitch -Name LAN -EnableSoftwareRsc $false
                              This disables RSC, re run first command to confirm it is disabled

                              If your vSwitch has a space in the name add "" around the name
                              Get-VMSwitch -Name "WAN #1" | Select-Object RSC

                              After applying speed is back to normal but pfsense seems to top out showing throughput at 60mb, even though I was getting over 500mb.

                              Anyhow, hope it helps thers on Hyper-V (this is a 2019 instance of Hyper-V)

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                              • D
                                DonZalmrol @RMH 0
                                last edited by DonZalmrol

                                @rmh-0 fantastic find!

                                I can confirm this has resolved it for me to, I'll leave it as is until a fix comes out.

                                Speed with RSC enabled:
                                aa9d7a1f-03e1-4815-8854-27b95d33d70f-image.png

                                Speed with RSC disabled:
                                063932be-5af6-48e6-9189-946fb1ed99c3-image.png

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                                • Bob.DigB
                                  Bob.Dig LAYER 8
                                  last edited by

                                  Disabling RSC did nothing good for me at least. Problem with super slow SMB-Share over VLAN persists.

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                                  • stephenw10S
                                    stephenw10 Netgate Administrator
                                    last edited by

                                    Mmm, RSC is TCP only so I guess that explains why you saw much better throughput with a UDP VPN.
                                    But I'm unsure how the pfSense update would trigger that...

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                                      DonZalmrol @stephenw10
                                      last edited by

                                      @stephenw10 maybe with the new FreeBSD kernel release it activated some incompatible functions for Windows Server on a network card level? e.g. thanks to @RMH-0 I disabled RSC and it returned to a normal level.

                                      I know that about 7 years ago I needed to turn off VMQ in a large environment due to a bug in it that caused the guest VMs to all work incredibly slow...

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                                        RMH 0 @DonZalmrol
                                        last edited by

                                        @donzalmrol If you do not mind a quick query as yours is OK now. Do you get a similar representation of throughput in pfsense in comparison to the spee test.

                                        I get the below which is way different. Trying to see if I have another issue or if others have the same.

                                        Speed.png

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                                        • P
                                          PaulPrior
                                          last edited by

                                          Disabling RSC did nothing for my environment. Inter-vLAN rate are still a fraction of what they were. Between machines on the same vLAN a file copy takes 3 seconds, between vLANs via the pfSense this jumps to 45-90 minutes.
                                          ce0bdc46-a06f-4d01-a6de-5b1294b917ae-image.png

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                                          • P
                                            PaulPrior @PaulPrior
                                            last edited by

                                            @paulprior This is a file copy in action between vLANs. There are 10Gb\s virtual adapters!
                                            3f1128cd-6128-4a0a-9cc8-77b7f99a6946-image.png

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