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    [RESOLVED]No internet on ubuntu when disable dhcp

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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by johnpoz

      Yes lets see the output of the commands.. Not just you saying something doesn't work via what a browser? ping pfsense dmz address, if you can't then your never getting anywhere.. If you can not query dns then your never going to get anywhere via fqdn.

      Lets see say a traceroute when it works, and when it doesn't work to both an IP say 8.8.8.8 and then say via a fqdn like www.google.com

      Your not doing something like static arps are you in pfsense?

      If you setup a static arp say for 1.2.3.4 mac xyz so that what the client gets when dhcp is on, and then you setup IP on the machine to be 1.2.3.5 then no it wouldn't work.

      An intelligent man is sometimes forced to be drunk to spend time with his fools
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      • F
        Farisse @johnpoz
        last edited by Farisse

        @johnpoz
        the video is uploading i'll add screenshots in a few minutes
        https://streamable.com/j30bzs

        Ping from Windows Hyper-v to DMZ network 455fbd6a-2e49-4aca-9c16-51e06309c41e-image.png

        Ping from Ubuntu to DNS/DMZ network + ifconfig
        41793422-93b4-41ea-b546-d88f9cc70877-image.png

        Do you need more info ?

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          And that is with dhcp or static? And where is your dns query?

          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
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          • F
            Farisse
            last edited by Farisse

            This is Static the video is when internet was functional and then after reboot ... nothing anymore

            here is the dns query:
            c3cd78d9-8c96-438e-890e-4835863518f0-image.png

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by johnpoz

              Well not really possible to use the internet without dns resolution..

              What server are you trying to query - can not tell from that command..

              Do a dig with with @ipaddress of dns server.

              something like dig @192.168.1.1 www.google.com

              your command is just going to ask some dns server, which don't know what that is for 192.168.1.1

              Is pfsense listening on dmz interface for dns? Are you pointing dns to something else?

              how about this output

              networkctl status
              ●        State: routable
                     Address: 192.168.2.12 on ens3
                              fe80::11:32ff:fe22:cc7d on ens3
                     Gateway: 192.168.2.253 (ADI Engineering, Inc.) on ens3
                         DNS: 192.168.3.10
              Search Domains: local.lan
                         NTP: 192.168.3.32
                              192.168.2.253
              

              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
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              • F
                Farisse @johnpoz
                last edited by

                @johnpoz Well i didn't change anything and i have an internet connection again.

                maybe extra information :
                I use an external DNS in pfsense
                25f8f886-96b7-48a5-ad05-9bf473fc797e-image.png

                As from now i have internet this is the requested command :
                2e919bed-ce19-4c6b-a4c7-be3a8079fe0c-image.png

                cdea2864-c329-4214-bd3d-60812506f9b0-image.png

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  Well from your output of nteworkctl you have NO DNS set..

                  Unless you setup forwarding on pfsense, those dns servers don't do anything other what pfsense itself would use for dns.

                  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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                  • F
                    Farisse
                    last edited by

                    The DNS forwarder is indeed enabled in pfsense and dns resolver to. Does it make any change if i configure the dns on a client machine ?

                    And why do i get internet for a few time then no more internet and after a few time back again without changing nothing ?

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      My "guess" would be when your on dhcp you cache some records..

                      Clearly from what you posted you have no dns set.. So NO internet is never going to work - unless you plan on just using IPs only ;)

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

                        @Farisse said in No internet on ubuntu when disable dhcp:

                        The DNS forwarder is indeed enabled in pfsense and dns resolver to

                        Well that is just borked! You mean you have unbound fowarding? Running both forward (dnsmasq) and resolver unbound is going to be problematic for sure.. Unless you have 1 running on different port than 53.

                        from your directed query to 192.168.1.1 you resolved google - so set your ubuntu to use that for its dns when you run static.

                        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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                        • F
                          Farisse
                          last edited by

                          They are on two different ports
                          92a0187a-0d46-47c6-81eb-425c49f9b715-image.png
                          90899a5d-f29b-4944-bfaa-6c614e19fe02-image.png

                          I should normally not have any problem with that ? Except maybe my other dns server who is in my lan that i use with freeradius on my guest network ?

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                          • F
                            Farisse @johnpoz
                            last edited by

                            @johnpoz said in No internet on ubuntu when disable dhcp:

                            from your directed query to 192.168.1.1 you resolved google - so set your ubuntu to use that for its dns when you run static.

                            What do you mean with this ? I thought i already configures my ubuntu for using a dns ?
                            c6e5b648-ab3c-49db-9213-05f9dfa9cf4d-image.png
                            286efefb-6daa-4f00-af26-9316acdd2e85-image.png

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                            • johnpozJ
                              johnpoz LAYER 8 Global Moderator
                              last edited by johnpoz

                              Well clearly not using that now is it..

                              When you directed to do dns it work @192.168.1.1

                              When you just do dig, its saying it can not talk to dns.

                              when you look with networkctrl status - does it show you dns.. NO... And its not working, so clearly its NOT SET!! if it was, then it would be using it and working...

                              what does nslookup show you?

                              user@NewUC:~$ nslookup www.google.com
                              Server:         127.0.0.53
                              Address:        127.0.0.53#53
                              
                              Non-authoritative answer:
                              Name:   www.google.com
                              Address: 172.217.4.196
                              Name:   www.google.com
                              Address: 2607:f8b0:4009:806::2004
                              
                              

                              Here
                              https://linuxize.com/post/how-to-configure-static-ip-address-on-ubuntu-18-04/

                              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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                              • F
                                Farisse
                                last edited by Farisse

                                Yeah you’re right it should work if it was set do not understand why it doesn’t.

                                Btw thank you for the link but I can’t process as it is explained. I removed netplan to use the old network configuration ( using /etc/network/interfaces & the screenshot above for the dns)

                                This is the result of the requested command

                                3243C0C6-218B-442F-B30F-5AB68AB3D35A.png

                                alt text

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                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator
                                  last edited by

                                  So from your nslookup its working, but its pointing to dnsmasq most likely running locally.. Which in turn forwards to whatever dns you want say 192.168.1.1

                                  So now it should be working?

                                  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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                                  • F
                                    Farisse
                                    last edited by

                                    Ubuntu is insane haha >.< You set up everything to be used 'externally' and it choose to use local dnsmasq. Whatever ...

                                    It is working indeed, i'm just afraid to restart the machine and lose the connection again. i prefered to follow what you said to check everything and if its not working anymore search from where it doesn't work. So i'm going to restart now and hope it will still work.

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                                    • F
                                      Farisse
                                      last edited by

                                      as i thought after a restart of the machine. No connectivity anymore. 😅

                                      ddb286f6-2cf6-48b9-b15b-0cc98222b079-image.png

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                                      • johnpozJ
                                        johnpoz LAYER 8 Global Moderator
                                        last edited by

                                        dude if you can not ping 192.168.1.1 then no you can not do anything...

                                        which has ZERO to do with dhcp, and really zero to do with pfsense at all.. You have other devices on this 192.168.1/24 network... I suggest you head on over to ubuntu forums in your native language to get help on how to setup it up with static..

                                        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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                                        • F
                                          Farisse
                                          last edited by

                                          Ok, Well thank you for your help. I already tried in my native language on ubuntu forum, but i got no answer. Whatever, i'll search after how to make it work.

                                          Thank you for your explanations, help & time ! 💯

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                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator
                                            last edited by

                                            Here is 1st thing you have to test when doing any basic networking troubleshooting.

                                            Can you actually talk to your gateway.. Can you talk to other devices on that network?

                                            If you can not, look in your arp table - you can not talk to ip address xyz, if you can not arp for it..

                                            DHCP has zero to do with actually connectivity - other than handing the client an IP, gateway and dns.. If your doing it static dhcp being on or off on the firewall has nothing to do with connectivity.

                                            If you say it works via dhcp, but not when static - then your not setting up the static correctly... The only way dhcp could have anything to do with your problem is if you were setting up static arp on pfsense. With a reservation that mac address xyz gets 1.2.3.4.. And now when not using dhcp you setup 1.2.3.5 so your static arp does not match up.. So you can not talk to pfsense would = broken connectivity.. Simple test of ping and knowing if you setup static arp or not would be key here..

                                            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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