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    Strange DHCP issue. Assigned /8 instead /24 on Linux devices.

    Scheduled Pinned Locked Moved DHCP and DNS
    dhcp 8 24
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    • kiokomanK
      kiokoman LAYER 8
      last edited by

      which IP is assigned to you exactly?
      did you try with dhclient -v from the terminal to see who is releasing that ?
      DHCPACK should tell you

      ̿' ̿'\̵͇̿̿\з=(◕_◕)=ε/̵͇̿̿/'̿'̿ ̿
      Please do not use chat/PM to ask for help
      we must focus on silencing this @guest character. we must make up lies and alter the copyrights !
      Don't forget to Upvote with the 👍 button for any post you find to be helpful.

      L 1 Reply Last reply Reply Quote 1
      • L
        lazy @kiokoman
        last edited by lazy

        @kiokoman

        Internet Systems Consortium DHCP Client 4.4.1
        Copyright 2004-2018 Internet Systems Consortium.
        All rights reserved.
        For info, please visit https://www.isc.org/software/dhcp/
        
        Listening on LPF/wlan0/ba:ef:(cleared)
        Sending on   LPF/wlan0/ba:ef:(cleared)
        Listening on LPF/eth0/74:d0:(cleared)
        Sending on   LPF/eth0/74:d0:(cleared)
        Sending on   Socket/fallback
        DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 3
        DHCPREQUEST for 10.35.163.174 on eth0 to 255.255.255.255 port 67
        DHCPACK of 10.35.163.174 from 10.35.163.1
        bound to 10.35.163.174 -- renewal in 3213 seconds.
        
        eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
            link/ether 74:d0:(cleared) brd ff:ff:ff:ff:ff:ff
            inet 10.35.163.174/32 scope global dynamic eth0
               valid_lft 6717sec preferred_lft 6717sec
            inet6 2001:470:(cleared) scope global dynamic noprefixroute 
               valid_lft 7194sec preferred_lft 4494sec
            inet6 2001:470(cleared) scope global dynamic noprefixroute 
               valid_lft 86398sec preferred_lft 14398sec
            inet6 fe80::(cleared) scope link noprefixroute 
               valid_lft forever preferred_lft forever
        
        

        10.35.163.1 - my pfsense build.

        before "dhclient -v" i can't receive any ipv4 address via dhcp on this host.

        network still not working :(

        1 Reply Last reply Reply Quote 0
        • kiokomanK
          kiokoman LAYER 8
          last edited by

          ping 8.8.8.8 ?
          route -4 ?
          post firewall rules of pfsense

          ̿' ̿'\̵͇̿̿\з=(◕_◕)=ε/̵͇̿̿/'̿'̿ ̿
          Please do not use chat/PM to ask for help
          we must focus on silencing this @guest character. we must make up lies and alter the copyrights !
          Don't forget to Upvote with the 👍 button for any post you find to be helpful.

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          • L
            lazy @kiokoman
            last edited by lazy

            @kiokoman

            ping not working

            route -4 has nothing
            firewall rules here:
            (deleted)

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            • L
              lazy @kiokoman
              last edited by lazy

              @kiokoman today i checked all once again, and i see that the 255.0.0.0 mask was assign to windows machines too, but in settings of DHCP server (and lan interface too) installed a 255.255.255.0 mask... How that work?

              2020-02-02_20-44-37.png

              1 Reply Last reply Reply Quote 0
              • kiokomanK
                kiokoman LAYER 8
                last edited by

                if you can plug something directly to the lan of pfsense to see if it works, maybe there is something wrong on the switch

                ̿' ̿'\̵͇̿̿\з=(◕_◕)=ε/̵͇̿̿/'̿'̿ ̿
                Please do not use chat/PM to ask for help
                we must focus on silencing this @guest character. we must make up lies and alter the copyrights !
                Don't forget to Upvote with the 👍 button for any post you find to be helpful.

                L 1 Reply Last reply Reply Quote 1
                • DerelictD
                  Derelict LAYER 8 Netgate
                  last edited by

                  You probably have another DHCP server on your network.

                  Packet capture the port 67 traffic and wireshark will tell you exactly what DHCP is doing. Pay close attention to what MAC address is sending what.

                  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)

                  L 1 Reply Last reply Reply Quote 1
                  • L
                    lazy @kiokoman
                    last edited by

                    @kiokoman i'm tied, nothing changes...

                    1 Reply Last reply Reply Quote 0
                    • L
                      lazy @Derelict
                      last edited by

                      @Derelict said in Strange DHCP issue. Assigned /8 instead /24 on Linux devices.:

                      Packet capture the port 67 traffic and wireshark will tell you exactly what DHCP is doing.

                      Tried it too. PFSense is only the one dhcp server in the my network... :(

                      1 Reply Last reply Reply Quote 0
                      • chpalmerC
                        chpalmer
                        last edited by

                        You don't have anything configured under "Additional BOOTP/DHCP Options" do you?

                        Triggering snowflakes one by one..
                        Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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

                          Post the packet capture of a complete DHCP exchange. If the DHCP server is sending /24 and the clients are setting /8 there is nothing the DHCP server can do about it.

                          Also post the contents of /var/dhcpd/etc/dhcpd.conf from the pfSense node.

                          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)

                          L 1 Reply Last reply Reply Quote 1
                          • L
                            lazy @Derelict
                            last edited by lazy

                            @Derelict
                            wireshark capture: (deleted)

                            dhcp.conf (deleted)

                            I cleared private data from dhcp.conf

                            @chpalmer nothing in Additional settings.

                            JKnottJ 1 Reply Last reply Reply Quote 0
                            • chpalmerC
                              chpalmer
                              last edited by

                              Go back into the settings of your padavan units and verify that the DHCP servers are truly turned off.

                              Go into your switches and verify that the DCHP servers are truly turned off.

                              Triggering snowflakes one by one..
                              Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

                              L 1 Reply Last reply Reply Quote 1
                              • L
                                lazy @chpalmer
                                last edited by

                                @chpalmer shure, it's already done...
                                No active DHCP servers on my padavan units (configured as access points), switches (it's not have a dhcp server options), and on my synology unit too...

                                chpalmerC 1 Reply Last reply Reply Quote 0
                                • chpalmerC
                                  chpalmer @lazy
                                  last edited by

                                  @lazy

                                  I confused the DGS1100 and the DGS1510 which does have an available DHCP server..

                                  On the Padavan there is the option of Static IP assignment.. Is that also off?

                                  Are all your Linux devices you are testing wireless?

                                  Triggering snowflakes one by one..
                                  Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

                                  L 1 Reply Last reply Reply Quote 1
                                  • L
                                    lazy @chpalmer
                                    last edited by

                                    @chpalmer said in Strange DHCP issue. Assigned /8 instead /24 on Linux devices.:

                                    all your Linux devices you are testing wireless?

                                    2020-02-02_23-10-18.png
                                    It's not have anything about DHCP or address reservations. Configured as access point. Another padavan unit configured the same.

                                    I tested wireless and wired devices, nothing changes, but today i see that the windows device assigned 255.0.0.0 too. So, it's not a linux problem...

                                    1 Reply Last reply Reply Quote 0
                                    • chpalmerC
                                      chpalmer
                                      last edited by

                                      Quick test.. Unplug everything from your pfSense router. Or just turn it off.

                                      Reboot one of the devices that is getting wrong info. See if it gets an address.

                                      Triggering snowflakes one by one..
                                      Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

                                      L 1 Reply Last reply Reply Quote 1
                                      • L
                                        lazy @chpalmer
                                        last edited by

                                        @chpalmer tried it before, and it's not help, but, i will try it tomorrow again...
                                        Pfsense unit not in my room, and for now i can't access it phisicaly.

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

                                          @lazy said in Strange DHCP issue. Assigned /8 instead /24 on Linux devices.:

                                          wireshark capture: bootpwireshark.pcapng

                                          I don't see option 1, the subnet mask in there.

                                          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...

                                          L 1 Reply Last reply Reply Quote 1
                                          • L
                                            lazy @JKnott
                                            last edited by

                                            This post is deleted!
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