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    Dynamic IPv6 Prefix assignment issue in xDSL users

    Scheduled Pinned Locked Moved IPv6
    ipv6
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    • GrimsonG
      Grimson Banned @chaispaquichui
      last edited by

      @chaispaquichui said in Dynamic IPv6 Prefix assignment issue in xDSL users:

      "Yeah, just use a tunnel broker and add 10-15ms of latency for each ipv6 connexion, it's fine"

      So what? Those few ms won't kill you.

      NAT is ugly and has to die as fast as possible, reviving it for IPv6 would be more than stupid.

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      • johnpozJ
        johnpoz LAYER 8 Global Moderator
        last edited by johnpoz

        There is a HE pop in Amsterdam, NL - I doubt that is going to A 10-15ms to your path.. Maybe 2 or 3 tops.. Its only what 200 miles from one side of belgium to the other side of NL.. So yeah lets at worse call it 3 ms..

        Also one in Frankfort - about the same distance.. Paris as well isn't far from any point in Belgium... So you have like 3 that I know of that are what 3ms from anywhere you could be Belgium.. I could see your point if closest pop was 3000 miles away from you... But EU is pretty freaking tiny when it comes to total latency anywhere.. Adding 3ms is not going to be any sort of issue.

        Added bonus is the /48 you get.. You can use that on ANY isp you move too.. I have had the same /48 since 2013.. My current isp doesn't even have any ipv6.. Same addressing...

        That is going to be way better than doing some nonsense nat on ipv6 because your isp is stupid.

        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 2.7.2, 24.11

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        • DerelictD
          Derelict LAYER 8 Netgate @chaispaquichui
          last edited by Derelict

          @chaispaquichui said in Dynamic IPv6 Prefix assignment issue in xDSL users:

          "Yeah, just use a tunnel broker and add 10-15ms of latency for each ipv6 connexion, it's fine"

          No, it's not. I realy don't understand your attitude... Pfsense is already capable of doing static NPT, you know it's a thing and there is a feature request for dynamic NPT... You can implement it and solve this stupid issue...

          Your ISP can deploy IPv6 correctly and solve this stupid issue.

          Chattanooga, Tennessee, USA
          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
          Do Not Chat For Help! NO_WAN_EGRESS(TM)

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          • C
            chaispaquichui
            last edited by

            I understood you are not going the implement dynamic NPT but I will stand my case until the end !

            Thx for you answer jognpoz but ironically, I know this pop in Amsterdam... I used it during 2 years, before my ISP start giving me native IPv6 addresses. I know for a fact that it gives me 10 or 15 ms of extra latency, I experimented it :(

            "NAT is ugly and has to die as fast as possible, reviving it for IPv6 would be more than stupid."

            There is no such thing as an "evil" protocol. The NAT you are referring to is "'PAT", NPT is not the same.

            I'm not saying you should always do NAT with IPv6, far from it ! But NPT has some uses cases

            • You want to do IPv6 multihoming withouth BGP ? You can use NPT
            • You want to be able to leave your ISP without having to renumbered your LAN ? You can use NPT
            • You want to give the middle finger to greedy ISP who gives you dynamic prefix ? You can use NPT

            "That is going to be way better than doing some nonsense nat on ipv6 because your isp is stupid."

            It's not "nonsense", it's a solution to a real problem :( My ISP is not supid, he is greedy. If I want a static prefix, I can... I just need to pay 2 or 3 times the actual price of my connexion. And this ISP is not the first to do that and he is not going to be last.

            You know what is truly ironic ? I just discovered that pfsense is able to do PAT for IPv6 !

            0_1547304536611_79aa8f9c-def8-4bb3-97b5-d2d8e15462bc-image.png

            My problem is solved !

            But it's ugly and I don't want to do that... Pfsense can do static NPT and PAT for IPv6, please add dynamic NPT, it's less ugly

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            • C
              chaispaquichui
              last edited by chaispaquichui

              0_1547304942258_efdd7ed1-d0e5-4c29-927b-b046f4566e37-image.png

              Are you kidding me ?

              Edit : okey, thx for the clarification !

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              • NogBadTheBadN
                NogBadTheBad
                last edited by NogBadTheBad

                It could be the forum seeing you post from a different IP address, its not people disliking your post.

                https://forum.netgate.com/topic/137638/posts-being-marked-as-spam-on-my-lan

                Andy

                1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  Well its possible your ISP doesn't peer with HE and your taking a long path to get to that pop, try one of the other pops in EU that are also only about 200 some miles from anywhere in Belgium.

                  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 2.7.2, 24.11

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                  • demD
                    dem @Derelict
                    last edited by

                    If you need a firewall that will automatically track a changing prefix delegation and adjust firewall rules, etc, pfSense is not for you.

                    You should maybe put that on the SG-1100 product page. I bet tens of millions of residential users in the US can't get static IPv6.

                    @chaispaquichui Thank you for pointing out that NAT (or PAT, whatever) works fine with IPv6. Though ugly it solves a real problem, and perhaps allows Multi-WAN without static IPv6 from either provider.

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

                      Rules are dynamically adjusted for when the tracked prefix changes on the lan side interfaces, that is the whole point of using the built in "network" aliases... They allow you to create rules so even if the interfaces network changes the rules would allow clients in this new network to still be allowed through the rules, etc.

                      If you hard code a cidr and that network changes - that would be on you.

                      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 2.7.2, 24.11

                      DerelictD 1 Reply Last reply Reply Quote 0
                      • DerelictD
                        Derelict LAYER 8 Netgate @dem
                        last edited by

                        @dem said in Dynamic IPv6 Prefix assignment issue in xDSL users:

                        If you need a firewall that will automatically track a changing prefix delegation and adjust firewall rules, etc, pfSense is not for you.

                        You should maybe put that on the SG-1100 product page. I bet tens of millions of residential users in the US can't get static IPv6.

                        Right, but many providers understand how IPv6 works and honor the DUID and very, very rarely change the prefix delegation. A change in PD is nearly always due to mitigating circumstances, such as you changing the DUID you send.

                        I personally have dynamic IPv6 from Cox and get the same PD every time. This is because Cox "gets it."

                        Dynamic IPv6 works fine when properly-implemented at the ISP side. Have you complained to them? If they want to do something nonstandard, you might be relegated to using their "residential gateway" hardware if you choose to use them for ISP service.

                        @grimson said in Dynamic IPv6 Prefix assignment issue in xDSL users:

                        Many German ISPs actually enforce a regular IP change for IPv4 and prefix change for IPv6. That is intended by the ISPs because a fixed IP is a premium option for their business offerings.

                        This, if factual, is the problem. Not lack of documentation on the pfSense site. And this is nothing specific to the SG-1100.

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                        • DerelictD
                          Derelict LAYER 8 Netgate @johnpoz
                          last edited by Derelict

                          @johnpoz said in Dynamic IPv6 Prefix assignment issue in xDSL users:

                          Rules are dynamically adjusted for when the tracked prefix changes on the lan side interfaces, that is the whole point of using the built in "network" aliases... They allow you to create rules so even if the interfaces network changes the rules would allow clients in this new network to still be allowed through the rules, etc.

                          If you hard code a cidr and that network changes - that would be on you.

                          Right but that is only part of the problem.

                          Making things like DMZs you would have to take great care when blocking access to other local subnets. Since we can't just use the Block Everything RFC1918 hammer any more.

                          For instance you could get a /56 PD and route a /60 or whatever to a downstream switch. That would not be contained in any interface subnet auto-alias. So there's another place that would need to be changed when a PD was maliciously changed by the ISP. I'm sure there are hundreds of places.

                          The whole point is to put public addresses everywhere on the inside. This type of behavior is unheard of in the IPv4 space. Why should it be tolerated in IPv6?

                          ISPs should not change PDs willy-nilly or should be killed by customer dissatisfaction and churn.

                          Chattanooga, Tennessee, USA
                          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                          Do Not Chat For Help! NO_WAN_EGRESS(TM)

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

                            @derelict said in Dynamic IPv6 Prefix assignment issue in xDSL users:

                            ISPs should not change PDs willy-nilly or should be killed by customer dissatisfaction and churn.

                            Yup completely agree!!! Once they give me my /48 it should be mine until I am no longer a customer.. It should never change.. If they only want to give a /56 or even a /60 ok... But once given to me, it should never change..

                            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 2.7.2, 24.11

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                            • P
                              pfadmin
                              last edited by

                              with duid telekom change the IPv6 rarely, but it changes. Thats reality, a fact we can not change. So ignore the users, it's ok. Or do a little bit of coding! Give us an alias which I can add to my rules. I can build my rules with this alias and have not to look and change manualy. And give this alias to DNS Resolver where I can build the server IP with alias and known interface identifyer. We can discus what one of the biggest telko should do or not or we can just solve the problems/wishes of potentialy millions of users in europe.

                              thanks

                              DerelictD 1 Reply Last reply Reply Quote 0
                              • DerelictD
                                Derelict LAYER 8 Netgate @pfadmin
                                last edited by

                                @pfadmin Pull requests are always appreciated.

                                Chattanooga, Tennessee, USA
                                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                • P
                                  pfadmin
                                  last edited by

                                  one of those:

                                  https://redmine.pfsense.org/issues/6626

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                                  • DerelictD
                                    Derelict LAYER 8 Netgate
                                    last edited by

                                    A feature request is not a pull request.

                                    A pull request is "here's proposed code to implement/fix this."

                                    Chattanooga, Tennessee, USA
                                    A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                    DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                    Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                    • C
                                      chaispaquichui
                                      last edited by

                                      I really don't understand... You could solve this problem and use it for marketing purpose...

                                      Something like "Yep, we know some ISP give you a dynamic prefix but don't worry, pfsense as a solution for that !"

                                      Instead, you completely ignore the users and tell them to complain to the ISP (who doesn't care because it's their business model)

                                      Anyway, it's not important anymore. I switched to OPNsense. They have a ticket for this problem and are working on it.

                                      https://github.com/opnsense/core/issues/2544

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

                                        @chaispaquichui said in Dynamic IPv6 Prefix assignment issue in xDSL users:

                                        Instead, you completely ignore the users and tell them to complain to the ISP (who doesn't care because it's their business model)

                                        How is pfSense supposed to fix something that's been broken by the ISP? If they change your prefix, you can't keep using the old one. This means any existing connections will break. As for more than one address, the normal operation with SLAAC is to use privacy addresses for outgoing connections. These will change daily, but remain within the prefix. There is also a fixed address that does not change daily and can be used for incoming connections. It does not matter if the privacy address changes daily, as a new connection will always use the newest. Older ones remain for a week, to support any existing connection. So, the problem is not that you have multiple addresses, but that the addresses are in different prefixes. That is entirely the ISP's doing. They are the ones that are breaking how IPv6 is supposed to work.

                                        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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                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator
                                          last edited by johnpoz

                                          And to be honest - any sort of work around on the part of pfsense or any router distro doesn't do anyone any favors at all.. Since it just allows the ISP to remain broken..

                                          Broken or half assed deployments doesn't help promote the movement to IPv6... it just slows it down even more..

                                          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 2.7.2, 24.11

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                                          • B
                                            bimmerdriver
                                            last edited by

                                            It's kind of funny seeing comments such as "the ISP has a broken implementation of IPv6" or "you should change your ISP". I wonder what world you guys who suggest these things are living in. Most people have few choices for ISP. For example, my ISP is Telus, which has a somewhat interesting implementation of IPv6. I have a contact in the engineering department who is surprisingly candid about their design decisions. He doesn't necessarily agree with them, but at least he is open to discuss things such as prefixes. IF I don't like Telus, there is Shaw which doesn't support IPv6 at all.

                                            As was said, many ISPs force prefix changes, in order to extract extra $$ from the customers who want stable prefixes. Most ISPs have no f*cks to give if you say you will switch unless they "fix" things that their subscribers consider to be broken. For most people, the first and only point of contact is telephone support, which might be outsourced to a third-world country. Does anyone seriously think complaining to Rajinder will change anything?

                                            As for using a tunnel, Hurricane Electric is maybe the only ISP in the world that listens to feedback. I wish they offered full internet service. If they did, I would pay more to use them. A tunnel is a good way to get IPv6 if you have no other choice, but it has limitations. For one, Netflix doesn't work over it. For another, unless HE's server is in the same city where you live, it tends to mess up location specific websites.

                                            ISPs are widely known for providing terrible service and that's not going to change because they are listening to their subscribers. This is why people ask for pfSense to help "fix" things that the ISP got wrong.

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