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    DNS across VLANS

    Scheduled Pinned Locked Moved DHCP and DNS
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    • GertjanG
      Gertjan @A Former User
      last edited by

      @angdigi said in DNS across VLANS:

      Tower is static IP

      and in that case the Resolver doesn't know anything about that device.
      So, nothing in his cache, so his name can't be resolved by no-body - not on LAN, not on any OPTx interface neither.

      I advise you to never touch the Interface settings on a device that you buy (PC, tablet, server, door-bell, coffee machine, whatever). Leave DHCP-client on.
      If you want a device to have always the same IP (gateway, etc); go edit the device that hands over IP's : our pfSens and Static-DHCP map all these devices.
      Check also "Static DHCP" on the Resolver settings page.
      Done - and everything is manged centralized - with big bonus : DNS (Resolving) works right away.

      IPv6 ? same thing !!

      No "help me" PM's please. Use the forum, the community will thank you.
      Edit : and where are the logs ??

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      • ?
        A Former User
        last edited by

        I see.

        So I have Static DHCP checked on the Resolver settings page.

        Are you referring to DHCP Server -> DHCP Static Mappings for this Interface?
        Is the attached image correct?
        0_1538753593891_Capture.JPG

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        • GertjanG
          Gertjan
          last edited by

          Exact.
          Do this for every host on every LAN (DHCP server instance) for which you want a "fixed" IP.

          No "help me" PM's please. Use the forum, the community will thank you.
          Edit : and where are the logs ??

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          • ?
            A Former User
            last edited by

            Will do.

            What about situations where there is no MAC address, i.e docker containers?

            GertjanG 1 Reply Last reply Reply Quote 0
            • GertjanG
              Gertjan @A Former User
              last edited by

              @angdigi said in DNS across VLANS:

              docker containers?

              Is a "docker" a piece of hardware with a NIC and thus a MAC ?
              Does a "docker" asks for a IP ? ;)

              No "help me" PM's please. Use the forum, the community will thank you.
              Edit : and where are the logs ??

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                a docker is like a VM so to speak, normally behind a nat to be honest where there is like a port forward a port into the IP the docker is running on.

                All depends on how they setup their docker networking..

                Anything that you are setting up an IP or behind some other IP that you want to resolve to a fqdn - just use a host override.

                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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                • ?
                  A Former User
                  last edited by A Former User

                  It does ask for an IP but I believe from its own built-in dhcp server...
                  Not sure how to answer the first question...mostly in fear of sounding stupid.

                  EDIT: sorry @johnpoz didn't see your response as I had the reply window open

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    Be default your prob going to get an IP in the 172.17/16 range

                    https://docs.docker.com/network/network-tutorial-standalone/

                    Yes they will have MAC addresses - but normally out of the box they behind a nat..

                    You can view your details.. Here is a couple running on my nas

                    sh-4.3# docker network inspect bridge
                    [
                        {
                            "Name": "bridge",
                            "Id": "7be1221de1c3abee70e138ed0651a44986e105bba3031cab7f2c4f3eac945fb8",
                            "Created": "2018-09-27T13:15:49.356329988-05:00",
                            "Scope": "local",
                            "Driver": "bridge",
                            "EnableIPv6": false,
                            "IPAM": {
                                "Driver": "default",
                                "Options": null,
                                "Config": [
                                    {
                                        "Subnet": "172.17.0.0/16",
                                        "Gateway": "172.17.0.1"
                                    }
                                ]
                            },
                            "Internal": false,
                            "Attachable": false,
                            "Ingress": false,
                            "Containers": {
                                "72ac978be5bbd94d6a2d018fbb730664eb96e18913603c4b2952397739de8324": {
                                    "Name": "ninthwalker-nowshowing1",
                                    "EndpointID": "b154b1170d53b75c517e9181977ee5869fe328ae8838ac030161ecf5ab3d6421",
                                    "MacAddress": "02:42:ac:11:00:03",
                                    "IPv4Address": "172.17.0.3/16",
                                    "IPv6Address": ""
                                },
                                "99fdcb2f1e965566e80f12b460d40d2454e0adf7461e8b185268bc17feae943a": {
                                    "Name": "tautulli-tautulli1",
                                    "EndpointID": "a0342da5a95109d801546e5d653c312c75cad5dac16a58c1e40d27930188a2c7",
                                    "MacAddress": "02:42:ac:11:00:02",
                                    "IPv4Address": "172.17.0.2/16",
                                    "IPv6Address": ""
                                }
                            },
                            "Options": {
                                "com.docker.network.bridge.default_bridge": "true",
                                "com.docker.network.bridge.enable_icc": "true",
                                "com.docker.network.bridge.enable_ip_masquerade": "true",
                                "com.docker.network.bridge.host_binding_ipv4": "0.0.0.0",
                                "com.docker.network.bridge.name": "docker0",
                                "com.docker.network.driver.mtu": "1500"
                            },
                            "Labels": {}
                        }
                    ]
                    sh-4.3#
                    

                    As you see the different containers have their own mac - but they also have an IP that is on the 172.17/16 network..

                    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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                    • ?
                      A Former User
                      last edited by

                      Thanks. Much better understanding now.

                      So for dockers, I'll add a host override. For VMs, PCs, tablets, cameras, etc...I'll add the DHCP static mapping.

                      I added a VM to VL20 and assigned a static mapping. Back to question 2 of the first post, is it possible to reach the device (in LAN) without using "local.lan"?

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                      • johnpozJ
                        johnpoz LAYER 8 Global Moderator
                        last edited by

                        That would depend on what your client uses for a search suffix.. If your too lazy to use a FQDN.. But dns doesn't answer unless its a FQDN..

                        but for example I use local lan and it is the default search suffix so sure I can resolve stuff by just putting in the host name..

                        C:>ping nas

                        Pinging nas.local.lan [192.168.9.10] with 32 bytes of data:
                        Reply from 192.168.9.10: bytes=32 time<1ms TTL=64
                        Reply from 192.168.9.10: bytes=32 time<1ms TTL=64
                        Reply from 192.168.9.10: bytes=32 time<1ms TTL=64
                        Reply from 192.168.9.10: bytes=32 time<1ms TTL=64

                        Ping statistics for 192.168.9.10:
                        Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
                        Approximate round trip times in milli-seconds:
                        Minimum = 0ms, Maximum = 0ms, Average = 0ms

                        C:>

                        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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                        • ?
                          A Former User
                          last edited by

                          I see.

                          So my LAN is the default search suffix as well
                          My VL20 is vpn.local.lan (I actually took your advice from another thread and added "vpn" to keep all VLANs organized)

                          Since I changed vl20 from the default, I won't be able to just use the hostname, correct? Its not a problem if I can't..just want to know expected behavior and best practice.

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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by

                            you can query them by just host name if you add more search suffix, you can have more than 1 and put them in order.. Your box will just do multiple queries with each suffix.

                            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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