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    Comcast Gigabit - SG-3100 (not getting gig speed)

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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      Simple google for sg3100 benchmarks on google shows multiple videos of it doing gig without any issues.. Even with ips on, etc.

      So no clue to where he is coming from..

      An intelligent man is sometimes forced to be drunk to spend time with his fools
      If you get confused: Listen to the Music Play
      Please don't Chat/PM me for help, unless mod related
      SG-4860 24.11 | Lab VMs 2.8, 24.11

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        cparkervt @johnpoz
        last edited by

        @johnpoz Oh I'm very well aware it can do gig, that's what lead me to purchase the SG-3100 however something is gumming up the works and I'm grasping at straws.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          I would suggest you take internet out of the equation to validate.. Simple iperf from something on wan to lan, versa.

          I have seen isp throuttle newer connections.. Connect some PC to your modem - can it do gig? This will have different mac than your previous router as well.

          An intelligent man is sometimes forced to be drunk to spend time with his fools
          If you get confused: Listen to the Music Play
          Please don't Chat/PM me for help, unless mod related
          SG-4860 24.11 | Lab VMs 2.8, 24.11

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            cparkervt @JohnKaul
            last edited by

            @JohnKaul I've been running iperf against the LAN IP of the pfSense and I'm getting roughly the same speeds so I don't suspect it's so much the routing part, but something else. I've been a user of pfSense since v1.2.3 and I've always loved it. This is just one of those gremlins... I used to be able to iperf to the old Dell running pfSense before at gig speeds, and through it (just not out to the internet) I can iperf through the Cisco SG200-26P switch at gig speeds minus overhead just fine.

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by

              testing to pfsense is not valid test of its routing/firewalling speed.

              You need to test "THROUGH" pfsense..

              An intelligent man is sometimes forced to be drunk to spend time with his fools
              If you get confused: Listen to the Music Play
              Please don't Chat/PM me for help, unless mod related
              SG-4860 24.11 | Lab VMs 2.8, 24.11

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              • J
                JohnKaul @cparkervt
                last edited by

                @cparkervt, Ah. cool. Thanks for the recommendation. I'm still on the fence to be honest. I've never used pfSense so I'm still reading (a lot) about it and the hardware. Thanks again though. I appreciate the recommendation.

                About the testing: iperf is a nice tool but read what @johnpoz just said.

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                  cparkervt @JohnKaul
                  last edited by

                  @JohnKaul @johnpoz I understand the logic about testing through the routing portion of pfSense but is there a specific reason why that's not a fair test? (not trying to be snarky; genuinely curious to learn why)

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                  • C
                    cparkervt @johnpoz
                    last edited by

                    @johnpoz said in Comcast Gigabit - SG-3100 (not getting gig speed):

                    I would suggest you take internet out of the equation to validate.. Simple iperf from something on wan to lan, versa.

                    I have seen isp throuttle newer connections.. Connect some PC to your modem - can it do gig? This will have different mac than your previous router as well.

                    I should have included this in my previous message. I have connected my MacBook to the modem directly, and set one of the IPs from my /29 public subnet AND tested with the DHCP lease received from the router portion of my modem. Both ways shows gig speed.

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      because pfsense stack for tcp is not meant to answer stuff asked of it, its meant to route it and firewall it... So no its not a fair test of what it can do.. Its not a server - its firewall/router.

                      An intelligent man is sometimes forced to be drunk to spend time with his fools
                      If you get confused: Listen to the Music Play
                      Please don't Chat/PM me for help, unless mod related
                      SG-4860 24.11 | Lab VMs 2.8, 24.11

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                      • J
                        JohnKaul @cparkervt
                        last edited by JohnKaul

                        @cparkervt, testing from a iperf client (laptop) to an iperf server (the 3100) would only be testing the cable/wifi signal (there's nothing in the way). The iperf server should be after the router so you test the throughput of the router.

                        After re-reading your posts, I think I misunderstood your last question. I apologize for the "lesson" (you already understand what I said above). Sorry.

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                        • A
                          akuma1x @johnpoz
                          last edited by

                          @johnpoz said in Comcast Gigabit - SG-3100 (not getting gig speed):

                          I would suggest you take internet out of the equation to validate.. Simple iperf from something on wan to lan, versa.

                          Are there any instructions anywhere on how to do this? All the talk of testing the routing THRU a pfsense box has me curious to setup this test.

                          I'm assuming it's a computer on the WAN port with some IP address, pfsense in the middle, and a machine on the LAN side. Run an iperf test and see the numbers. Anything more complicated than that?

                          Jeff

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by johnpoz

                            When you tested the speed of your switch, did you test through the switch or did you run iperf on the switch and talk to an SVI on the switch?

                            Nope thats it -

                            computer (iperf -s) --- pfsense ---- (iperf -c) computer

                            An intelligent man is sometimes forced to be drunk to spend time with his fools
                            If you get confused: Listen to the Music Play
                            Please don't Chat/PM me for help, unless mod related
                            SG-4860 24.11 | Lab VMs 2.8, 24.11

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                              cparkervt @johnpoz
                              last edited by

                              @johnpoz said in Comcast Gigabit - SG-3100 (not getting gig speed):

                              When you tested the speed of your switch, did you test through the switch or did you run iperf on the switch and talk to an SVI on the switch?

                              Nope thats it -

                              computer (iperf -s) --- pfsense ---- (iperf -c) computer

                              I will test PC -- OPT1 -- pfSense -- LAN1 -- PC ... later this evening.
                              Also on the agenda is testing a loaner SG-3100 with a virgin config.

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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator
                                last edited by

                                I would make sure you setup say opt1 to look like wan so its doing nat.. Since that could be a performance hit.. So you want to validate your speed is with natting being done.

                                An intelligent man is sometimes forced to be drunk to spend time with his fools
                                If you get confused: Listen to the Music Play
                                Please don't Chat/PM me for help, unless mod related
                                SG-4860 24.11 | Lab VMs 2.8, 24.11

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                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator
                                  last edited by

                                  lan by default is part of the switch right.. Possible you could have flood of broadcast traffic causing you issues on the switch?

                                  An intelligent man is sometimes forced to be drunk to spend time with his fools
                                  If you get confused: Listen to the Music Play
                                  Please don't Chat/PM me for help, unless mod related
                                  SG-4860 24.11 | Lab VMs 2.8, 24.11

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                                    cparkervt @johnpoz
                                    last edited by

                                    @johnpoz I'll isolate the pfSense from the rest of my network during testing. Just for grins, I tested from a LAN PC using iperf3 to an Ubiquiti EdgeRouter's WAN IP in that same /29 and I was getting ~300m but that could be that it's a cheap ER-X and not able to handle being an iperf server as I know those have potatoes for CPUs in them. 😉

                                    I appreciate all the help so far. I really hope it's something simple like "hey you missed this one thing" actually kind of enjoying the challenge (good thing this is my home office/ home lab)

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                                    • johnpozJ
                                      johnpoz LAYER 8 Global Moderator
                                      last edited by

                                      that brings up very good point... test your iperf server and client testing without pfsense to validate they can do gig..

                                      iperf -s --- wire ---- iperf -c

                                      or
                                      iperf -s --- switch ---- iperf -c

                                      And make sure you use all the wires you will use with the testing, before you put pfsense in the middle..

                                      If wasn't 3pm on a friday I would sim test the 3100 I have here.. But could do on monday ;)

                                      An intelligent man is sometimes forced to be drunk to spend time with his fools
                                      If you get confused: Listen to the Music Play
                                      Please don't Chat/PM me for help, unless mod related
                                      SG-4860 24.11 | Lab VMs 2.8, 24.11

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                                      • J
                                        JohnKaul @cparkervt
                                        last edited by

                                        @cparkervt said in Comcast Gigabit - SG-3100 (not getting gig speed):

                                        <snip> but that could be that it's a cheap ER-X and not able to handle being an iperf server as I know those have potatoes for CPUs in them. 😉 <snip>

                                        For what little it's worth: If I remember right, it's been a few years since I've dove into the source code but, iperf runs on the stack (memory) only. So you are running a memory<->memory network/performance test.

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                                          cparkervt @johnpoz
                                          last edited by

                                          @johnpoz Yeah all my other testing I've been doing to rule out my own network was random clients running iperf over my two Cisco SG200/300 switches and they get 900+. Hence my confusion as to why the pfSense LAN IP was getting almost exactly the same as my previously quoted Internet speed tests. But like I said, I'll isolate the pfSense and test routing/NAT performance via iperf and see what it says.

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                                            cparkervt
                                            last edited by cparkervt

                                            Isolated 3100.
                                            MacBook Pro used as iperf2 server.

                                            Through NAT:
                                            [332] 0.0- 1.0 sec 46.0 MBytes 386 Mbits/sec
                                            [332] 1.0- 2.0 sec 46.3 MBytes 388 Mbits/sec
                                            [332] 2.0- 3.0 sec 45.9 MBytes 385 Mbits/sec
                                            [332] 3.0- 4.0 sec 46.3 MBytes 388 Mbits/sec
                                            [332] 4.0- 5.0 sec 46.0 MBytes 386 Mbits/sec
                                            [332] 5.0- 6.0 sec 46.1 MBytes 387 Mbits/sec
                                            [332] 6.0- 7.0 sec 46.1 MBytes 387 Mbits/sec
                                            [332] 7.0- 8.0 sec 46.1 MBytes 387 Mbits/sec
                                            [332] 8.0- 9.0 sec 46.1 MBytes 387 Mbits/sec
                                            [332] 9.0-10.0 sec 45.9 MBytes 385 Mbits/sec
                                            [332] 0.0-10.0 sec 461 MBytes 386 Mbits/sec

                                            Through Comcast modem switch:
                                            [308] 0.0- 1.0 sec 117 MBytes 980 Mbits/sec
                                            [308] 1.0- 2.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 2.0- 3.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 3.0- 4.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 4.0- 5.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 5.0- 6.0 sec 113 MBytes 950 Mbits/sec
                                            [308] 6.0- 7.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 7.0- 8.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 8.0- 9.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 9.0-10.0 sec 113 MBytes 949 Mbits/sec
                                            [308] 0.0-10.0 sec 1.11 GBytes 951 Mbits/sec

                                            iperf3 was giving me weird numbers for both scenarios so I rolled back to iperf2.
                                            No special switches were used in either iperf test. Just -c and -s where appropriate.

                                            Weirdly enough I can hit ~650 presently via speedtest.net (I consistently use Boston Comcast as my target because that's my next hop before I hit the rest of the internet)

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