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    Not able to connect to some website

    Scheduled Pinned Locked Moved IPv6
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    • Bob.DigB
      Bob.Dig LAYER 8 @nonick
      last edited by Bob.Dig

      @nonick said in Not able to connect to some website:

      @jeff_wuyo WAN interface MTU + MSS entered correctly?

      I think you shouldn't reduce the value of MSS, it is done by pfSense, see the explanation under it.

      nonickN J 2 Replies Last reply Reply Quote 0
      • nonickN
        nonick @Bob.Dig
        last edited by

        @bob-dig said in Not able to connect to some website:

        I think you shouldn't reduce the value of MSS, it is done by pfSense, see the explanation under it.

        Unfortunately not, it's a bug in pfSense.

        Netgate 6100

        johnpozJ Bob.DigB 2 Replies Last reply Reply Quote 0
        • johnpozJ
          johnpoz LAYER 8 Global Moderator @nonick
          last edited by

          @nonick said in Not able to connect to some website:

          Unfortunately not, it's a bug in pfSense.

          And where is the redmine to that? I sure do not need to edit my mtu or mss values? Are you on some sort of say PPPoE connection or something where standard mtu does not work?

          Unless your on some isp connection that requires something lower, there should be no need to edit those.

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

            @nonick said in Not able to connect to some website:

            Unfortunately not, it's a bug in pfSense.

            Maybe it is fixed? That's why I think it is.

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            • J
              Jeff_WuYo @johnpoz
              last edited by

              @johnpoz said in Not able to connect to some website:

              but can tell you for sure if what you want is switch

              Yes, what I want is indeed switch. I also want to have different subnet, or rather different network to manage other device. Perhaps I should get a managed switch.

              huh? But you bridged them?

              Yeah, it's the way I figure out how to make all port have IPv6 connectivity. The way I do it is against my knowledge about how router and switch work, it just looks wrong. The machine which pfSense runs on has 4 ports, thus I want to make it works as router/switch. But if I bridged them and assign bridge0, only IPv4 worked, no IPv6 connectivity. Assigning bridge to me is more correct way to do it, but I'll lose IPv6.

              @nonick said in Not able to connect to some website:

              WAN interface MTU + MSS entered correctly?

              No. I leave it blank, which would be default. I'm not fully understand MTU and MSS, thus I ignore it for now.

              johnpozJ 1 Reply Last reply Reply Quote 0
              • johnpozJ
                johnpoz LAYER 8 Global Moderator @Jeff_WuYo
                last edited by johnpoz

                @jeff_wuyo said in Not able to connect to some website:

                Perhaps I should get a managed switch.

                Doesn't have to be a full managed switch, you can get a 8 port gig smart switch (does vlans) and some other limited features of a fully managed switch. For very reasonable price, there are many on the market in the $40 price range.

                But yes if your goal is to segment your network - a vlan capable switch is going to be be helpful ;) Next would be a access point that can also do vlans. If you want your wireless clients to be on different networks as well.

                While a bridge does have use cases, trying to turn interfaces into switch ports is not really a good use for a bridge. You can fry up a hamburger patty and "call" it steak - but its not a very "good" steak ;)

                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
                  Jeff_WuYo @johnpoz
                  last edited by

                  @johnpoz said in Not able to connect to some website:

                  trying to turn interfaces into switch ports is not really a good use for a bridge

                  That's true. I'm asking pfSense for too much lol.

                  The topic is altered.
                  Is the bridge-thingy I did causing my TLS connection to change? Hard to tell I think. I might reset pfSense and test again eventually. For now, I think I can still tinkering around.

                  johnpozJ 1 Reply Last reply Reply Quote 0
                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @Jeff_WuYo
                    last edited by

                    @jeff_wuyo said in Not able to connect to some website:

                    I'm asking pfSense for too much lol

                    Not so much that - but bridging is not switching. While it may mimic a switch in some aspects. Its not really switching..

                    There are some valid use cases where sure bridging is the solution - but wanting switch ports is not one of them ;)

                    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
                      Jeff_WuYo @Bob.Dig
                      last edited by

                      @bob-dig
                      I set my MTU 6000 on both WAN and LAN. The reason I chose big MTU is I always see some lost fragment package, and according to how IPv6 handle package exceed MTU, I assume that the package is large. I could be totally wrong, if so, please do correct me.
                      Beside the adjustment above, I didn't bridge any interface together this time.
                      For the sake of convenience, I just prepare the data I sniffed. Please use wireshark for more detail.

                      • File1
                        I was able to connect to archlinux, the handshake was successful, but not able load the site properly.
                        In this case, IPv6 for archlinux.org is [2a01:4f9:c010:6b1f::1]
                      • File2 is too large to upload, I put it at google drive.
                        In this example, I connect to multiple site, youtube.com [2404:6800:4012:2::200e], archlinux.org [2a01:4f9:c010:6b1f::1], and ipv6-test.com [multiple IPv6]. Only archlinux.org could not establish connection. Occasionally seeing pfSense complain to MyPC that the package is too large.

                      It seems like I always losing package from archlinux.org, as least that's what I saw on wireshark. Maybe wireshark is interpret the information wrong. Due to the lack of knowledge, I can't tell anymore form the data. I hope someone can point out a thing or two.

                      nonickN johnpozJ JKnottJ 3 Replies Last reply Reply Quote 0
                      • nonickN
                        nonick @Jeff_WuYo
                        last edited by nonick

                        @jeff_wuyo The maximum MTU for WAN-Interface is 1500 bytes (Ethernet maximum MTU size). With PPPoE connections, the PPPoE header increases the frame size by 8 bytes, so must lower the MTU to 1492.
                        You can test it with it, if it still doesn't work then set the MSS value additionally to 1452 or 1432.

                        Netgate 6100

                        J JKnottJ 2 Replies Last reply Reply Quote 0
                        • J
                          Jeff_WuYo @nonick
                          last edited by Jeff_WuYo

                          @nonick

                          Nope, didn't work. I set MTU to 1492 on WAN, MyPC just falls back to IPv4. Pure IPv6 site e.g. v6.facebook.com just can't connect. I can't ping using IPv6. Setting MSS to 1452 or 1432 doesn't help either.
                          Here's some test I run.
                          2f22396e-e582-48f7-8095-6cd6b4eb40ad-image.png
                          bdd59188-3e2c-48db-b6bc-963991853c07-image.png
                          4583c4c7-dbac-464f-81b4-e64555acb08e-image.png

                          @nonick said in Not able to connect to some website:

                          The maximum MTU for WAN-Interface is 1500 bytes

                          If that's so, why am I seeing package length way over 1500 when I setup my network as Modem/Router? Is wireshark just showing sum of multiple packages? (I should mention the Modem/Router is provided by my ISP, it's using PPPoE as well.) Here is an example.
                          81e67729-4a47-44c7-b95c-4e5e61b12c50-image.png

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator @Jeff_WuYo
                            last edited by

                            @jeff_wuyo said in Not able to connect to some website:

                            I set my MTU 6000 on both WAN and LAN.

                            Well no wonder your having issues.. That is just borked..

                            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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                            • JKnottJ
                              JKnott @Jeff_WuYo
                              last edited by

                              @jeff_wuyo said in Not able to connect to some website:

                              I set my MTU 6000 on both WAN and LAN.

                              While you can do what you want on your own LAN, you should go with what your ISP requires on the WAN side.

                              PfSense running on Qotom mini PC
                              i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                              UniFi AC-Lite access point

                              I haven't lost my mind. It's around here...somewhere...

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                              • JKnottJ
                                JKnott @nonick
                                last edited by

                                @nonick said in Not able to connect to some website:

                                (Ethernet maximum MTU size)

                                Not any more. That ended with frame expansion in the late '90s and these days jumbo frames of several KB are possible.

                                PfSense running on Qotom mini PC
                                i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                                UniFi AC-Lite access point

                                I haven't lost my mind. It's around here...somewhere...

                                johnpozJ nonickN 2 Replies Last reply Reply Quote 0
                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator @JKnott
                                  last edited by johnpoz

                                  @jknott said in Not able to connect to some website:

                                  jumbo frames of several KB are possible.

                                  While this is true - I highly doubt all his devices on his lan are using jumbo of 6000.. Devices like printer and for sure any iot normally have zero support for jumbo.

                                  And typical nics/drivers support only a couple of sizes..

                                  jumbo.jpg

                                  What I will say is pulling some arbitrary number like 6000 out of the air and setting your mtu to that is going to cause you grief that is for sure..

                                  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

                                  JKnottJ 1 Reply Last reply Reply Quote 0
                                  • nonickN
                                    nonick @JKnott
                                    last edited by nonick

                                    @jknott said in Not able to connect to some website:

                                    Not any more. That ended with frame expansion in the late '90s and these days jumbo frames of several KB are possible.

                                    That's right, I wrote on the WAN interface. 😉

                                    The maximum MTU for WAN-Interface is 1500 bytes

                                    Netgate 6100

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                                    • JKnottJ
                                      JKnott @johnpoz
                                      last edited by

                                      @johnpoz

                                      If one sets a DHCP server to provide whatever MTU size, wouldn't the device accept that value? I know there will be issues with WiFi. BTW, I've been around long enough to remember when 576 was a common MTU size.

                                      PfSense running on Qotom mini PC
                                      i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                                      UniFi AC-Lite access point

                                      I haven't lost my mind. It's around here...somewhere...

                                      johnpozJ 1 Reply Last reply Reply Quote 0
                                      • johnpozJ
                                        johnpoz LAYER 8 Global Moderator @JKnott
                                        last edited by

                                        @jknott said in Not able to connect to some website:

                                        provide whatever MTU size, wouldn't the device accept that value?

                                        No there is nothing saying they would even look or accept such values. Look at windows and search domain as perfect example. So option 119 of dhcp allows for assigning search domains, but not until windows 10 in a later build did windows accept such an option.

                                        Just because dhcp server offers the ability to hand out some option, doesn't mean clients would request or even accept an option. And stuff like iot devices normally have base min to "work" in their network stack anyway..

                                        Using non standard frame sizes is something that can really mess up a network if not all the devices are setup and validated to use and understand these non standard frame sizes. Just because say the switch will pass them, doesn't mean the device is smart enough to leverage or use them..

                                        And sure and the hell wouldn't use 6000?

                                        Can pretty much promise you issues he is seeing is related to such settings.. If anything PPPoE connection most likely would want something lower than the standard 1500 because of the overhead..

                                        I would suggest he moves his lan back to 1500, and then get with his ISP for the proper setup for his wan connection.. A common pppoe mss clamp size is like 1452.. But for optimal working with his ISP he should contact them for proper setup.

                                        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
                                          Jeff_WuYo
                                          last edited by Jeff_WuYo

                                          After I reset pfSense, and did a new setup, the issue still remain. I can't connect to archlinux.org via IPv6.

                                          @johnpoz said in Not able to connect to some website:

                                          I would suggest he moves his lan back to 1500, and then get with his ISP for the proper setup for his wan connection.. A common pppoe mss clamp size is like 1452.. But for optimal working with his ISP he should contact them for proper setup.

                                          I agree, I should consult my ISP for help. I left MTU and MSS default. Will it related to PMTUD no working? The last result might be using pfSense in transparent mode. I've never tested it yet.

                                          Another issue is ICMP req always failed (tested using ipv6-test.com), even I allow it on WAN interface. This didn't happen on my last configuration, which is pretty much the same as this one except I left DHPCv6 enable. I think I disable DHCPv6 last time, MyPC use RDNSS instead. I'm scratching my head off.

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