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

    Scheduled Pinned Locked Moved DHCP and DNS
    dhcp 8 24
    24 Posts 5 Posters 1.8k Views
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    • 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.

        L 2 Replies Last reply Reply Quote 1
        • L
          lazy @kiokoman
          last edited by lazy

          @kiokoman

          ping not working

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

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

                                            Sorry guys, totally my bad :(
                                            I'm not fully understand how works Additional DHCP settings in pfsense...
                                            At very strange situation, I have option "1" in Additional DHCP settings with parameter "text", and under this table was button "add", I think I need to push this button for take effect....
                                            I'm totally don't know how "1" was typed here, maybe my mistake (missclick), maybe something else...
                                            I removed "1" from the option, and then the correct mask was successfully assigned to my devices...

                                            I really want to make a death facepalm to myself.

                                            @chpalmer you was right!

                                            @JKnott thank you, I think I don't take attention to this parameter without your comment.

                                            Also, I deleted my dump and other files that may have my personal data.

                                            Thanks to all. This theme may be closed, and marked as solved.

                                            1 Reply Last reply Reply Quote 0
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