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    Dhcp lease client hostname missing (with 2.3)

    Scheduled Pinned Locked Moved DHCP and DNS
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    • A
      AsgardianFW
      last edited by

      So far this works at my smaller office.  I'm deploying the "fix" to a larger office for additional verification.

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      • V
        vynce
        last edited by

        This workaround fixed my two installations as well :D. I'll reply to the dhcp-users mailing list and hopefully we can come up with a proper fix for the next version of isc-dhcpd.

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        • C
          cmb
          last edited by

          I implemented that workaround for 2.3.2, since disabling the cache threshold won't have any impact on our users' use cases and it does appear to avoid the root cause problem.

          Thanks for getting the ball rolling on that one Vynce, had I realized a workaround would have come that easily, I'd have done so some time ago.

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          • A
            AsgardianFW
            last edited by

            Thanks Vynce for championing this effort with ISC.

            Thanks cmb for incorporating this into the next version.  I wasn't looking forward to remembering to patch this in manually after every upgrade.  I wish you the best of luck for whatever is next for you.

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            • V
              vynce
              last edited by

              Thanks Chris! I've opened a bug ticket in the isc-dhcp project to address the root issue: [ISC-Bugs #42849]. Their bug tracker appears to be closed to the public due to privacy concerns. Do we need to try and get some pfSense project email address added as a watcher? Not sure if you intend for the workaround to be reverted when the root issue is fixed…

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              • C
                cmb
                last edited by

                Thanks Vynce. Once it's fixed, please start a new ticket at redmine.pfsense.org to revert that change, as it would be preferable to go back to the default there once it doesn't break other things.

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                • V
                  vynce
                  last edited by

                  Sounds good, will do.

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                  • V
                    vynce
                    last edited by

                    Just a heads up that a patch for this issue has been committed to master in the isc-dhcp project and will be included in the isc-dhcp 4.3.5 beta. I will create a pfSense ticket to pull in isc-dhcp 4.3.5 final once it is released and revert Chris's workaround. I might try to build a pfSense-compatible dhcpd that includes this patch to verify the fix.

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                    • D
                      driiper
                      last edited by

                      I upgraded to 2.3.2 but are still having this issue with some of my boxes. I run a proxmox (KVM / LXC ) hypervisor. While the KVM boxes keeps their hostname in the dhcp records. The LXC boxes loses it after a while.

                      Do i have to do anything to apply this fix to a upgraded system (2.3.2)?

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                      • V
                        vynce
                        last edited by

                        You shouldn't have to do anything AFAIK. You can verify that the workaround is in place:

                        • Diagnostics -> Edit File.

                        • Paste "/var/dhcpd/etc/dhcpd.conf" in the box and click Load.

                        • Verify that dhcp-cache-threshold 0; is listed in the file.

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                        • V
                          vynce
                          last edited by

                          isc-dhcp 4.3.5 was released today and includes the fix for this issue. I've opened a new bug ticket to track upgrading to 4.3.5 and revert the workaround that Chris added.

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                          • R
                            rsq
                            last edited by

                            The workaround does not seem to be working for DHCPv6.

                            I verified that the workaround is in place in /etc/inc/services.inc . It appeared in 2 locations in the file.

                            Clients are ubuntu 14.04.3 LTS and 16.04 LTS.

                            On this version:
                            2.3.2-RELEASE-p1 (amd64)
                            built on Tue Sep 27 12:13:07 CDT 2016
                            FreeBSD 10.3-RELEASE-p9

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                            • MikeV7896M
                              MikeV7896
                              last edited by

                              @rsq:

                              The workaround does not seem to be working for DHCPv6.

                              In DHCPv6, the client does not provide its hostname to the DHCP server. The only form of identification is the DUID, a unique identifier that is generated by the operating system when the computer is set up. The only way a hostname is present under DHCPv6 is if it's a static entry, where you can enter a hostname yourself.

                              The S in IOT stands for Security

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                              • A
                                anschmid Banned
                                last edited by

                                I am on 2.3.3-p1 and have issues with missing hostnames.

                                Found this threat and checked if dhcp.conf has the "dhcp-cache-threshold 0;" and it doesn't.

                                Is this still needed or should this be fixed without the workaround?

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                                • V
                                  vynce
                                  last edited by

                                  The workaround is no longer needed since the root issue was fixed in isc-dhcp 4.3.5, which is included in pfSense 2.3.3. That's not to say there isn't some other issue causing missing hostnames, but I haven't seen a regression of this specific issue in pfSense 2.3.3.

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