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    Internet only subnet

    Scheduled Pinned Locked Moved IPv6
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    • G
      gwabber @johnpoz
      last edited by

      @johnpoz thanks for your reply!

      I indeed don't need any V6 networking on that VLAN, It works fine with V4. The reason I want to try it, is because I want to learn how to setup IPv6 and how the config is different from V4.
      For now I just leave it as is with IPv4, but I will make a seprate subnet to fiddle arround and see if I can create what I want with v6 :)

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

        @gwabber If its just a learning thing, there isn't much to learn really.. just create the rules you want.. There are many ways to skin the cat.. But again, the more specific you get with your allow/deny rules - the more rules you are going to have.

        if you want to allow specific this, and block specific that your not going to be able to do it with 1 rule ;)

        And to be honest, what does it matter if you have 10 rules or a 100 rules.. The more explicit the rules are, the more control you have - and to be honest the easier it is to read the rules.

        Creating rules with a aliases that allow this port and that port, and these Ips while ok can keep trim down your rules.. But why? When now when looking at them you have to figure out what exactly is in this alias, what is in that alias, etc.

        Just create your rules as specific as you want.

        if you don't want your specific network to be able to go to your wan IP address.. Then use the wan address in your firewall rule - this would include ipv6 and IPv4, be it gua or ula.. And if its link local, doesn't matter device on lan can not talk to the link-local address of the wan.

        While you could prob combine that into a IPv4+6 rule, if your goal is learning IPv6 - I wouldn't use combination rules, and would keep my IPv4 and IPv6 rules separate

        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

        Bob.DigB 1 Reply Last reply Reply Quote 0
        • Bob.DigB
          Bob.Dig LAYER 8 @johnpoz
          last edited by Bob.Dig

          @johnpoz Any thoughts why this (crosstalk between interfaces) is working, even with the WAN-gateway in the rule? I thought, back in the day, I have seen this stooping it even for IPv6.

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator @Bob.Dig
            last edited by johnpoz

            @Bob-Dig policy routing is going to force traffic only to that gateway.. Yeah that would block access to your other IPv6 networks, because your gateway your sending the traffic to can not get there.

            That would be the same for IPv4 or 6..

            Like I said there are many ways to skin the cat, you could have 1 set of rules that skins it one way, and another set of rules that skins it a different way.. You still end up with the same skinned cat ;)

            I personally wouldn't do it that way.. I like to be very explicit in what rules do, so the goal is easy to see.. Forcing traffic out a specific gateway might accomplish blocking client X from talking to destination Y.. But its not really clear that was the goal to the rule.. But if I have a specific rule that says X can not talk to Y.. Then its very clear what the point of that rule was.. Vs just a policy route - was the goal to block x from talking to y, or was the goal just to send traffic out a gateway.. Blocking x to y could be a byproduct of the rule - but is that something they actually wanted, or just something that happened.

            Explicit rules are always best.

            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

            Bob.DigB 1 Reply Last reply Reply Quote 0
            • Bob.DigB
              Bob.Dig LAYER 8 @johnpoz
              last edited by Bob.Dig

              @johnpoz said in Internet only subnet:

              policy routing is going to force traffic only to that gateway.. Yeah that would block access to your other IPv6 networks, because your gateway your sending the traffic to can not get there.

              But it is not working like my intention was. At least with ping, I can ping from my PC devices in the other subnet via IPv6 and vice versa...

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

                @Bob-Dig you sure you don't have an existing state? Or a rule say in floating that allows it..

                A ping to a dest where the pinger rules does not force out a gateway, would allow the return traffic even if where your pinging had a rule to force out a gateway.. because the state would be evaluated first, etc.

                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

                Bob.DigB 1 Reply Last reply Reply Quote 0
                • Bob.DigB
                  Bob.Dig LAYER 8 @johnpoz
                  last edited by

                  @johnpoz said in Internet only subnet:

                  you sure you don't have an existing state? Or a rule say in floating that allows it..

                  Yep, nothing.

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

                    @Bob-Dig It would take me a bit to duplicate the IPv6 stuff..

                    But can easy duplicate a policy route with IPv4 gateway..

                    2024-02-03_082237.jpg

                    Create a policy route rule to send traffic out my wan dhcp gateway..

                    I can not ping device on my other network.

                    Notice the rule has been evaluated.

                    Remove the rule and now I can ping..

                    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

                    Bob.DigB 1 Reply Last reply Reply Quote 0
                    • Bob.DigB
                      Bob.Dig LAYER 8 @johnpoz
                      last edited by

                      @johnpoz said in Internet only subnet:

                      It would take me a bit to duplicate the IPv6 stuff..

                      I wanted to try some linux machine but they all don't get an IPv6 address with their configuration so I am stuck with my windows machines for this test. But at least here it stands.

                      Now if you want to test this you probably have to disable the patch from the other thread but I am sure you have read this today.

                      1 Reply Last reply Reply Quote 0
                      • G
                        gwabber
                        last edited by

                        I guess I can do both... create rules to block traffic to my other subnets and a policy rule for the gateway. At least I have stuff to tinker with now!

                        Thanks!

                        Bob.DigB 1 Reply Last reply Reply Quote 0
                        • Bob.DigB
                          Bob.Dig LAYER 8 @gwabber
                          last edited by Bob.Dig

                          @gwabber said in Internet only subnet:

                          and a policy rule for the gateway. At least I have stuff to tinker with now!

                          If you want to tinker, try if the policy rule alone is preventing the crosstalk of the subnets with IPv6. For me it is only for IPv4 but my network is complicated.

                          G 1 Reply Last reply Reply Quote 0
                          • G
                            gwabber @Bob.Dig
                            last edited by

                            @Bob-Dig Gonna do that after the weekend! I will let you know!

                            G 1 Reply Last reply Reply Quote 0
                            • G
                              gwabber @gwabber
                              last edited by

                              @Bob-Dig sorry for my late reaction. Work was busy. The gateway rule does the trick with me!

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