• Bug#1109690: kea-dhcp4-server: fails to work after restarting networkin

    From Russell Coker@21:1/5 to All on Tue Jul 22 07:20:01 2025
    Package: kea-dhcp4-server
    Version: 2.6.3-1
    Severity: normal

    If networking.service is restarted (needrestart defaults to not restarting
    it but will list it in the services that need to restart to take the
    current configuration) then kea-dhcp4 won't work after that until it is restarted.

    I expect that the system will just sort it out. kea-dhcp4-server.service
    could be restarted by systemd as a dependency on networking it systemd
    was setup in that way. The kea process could just notice that the interface went down and up and it could reonfigure itself. A final option would be
    for the daemon to recognise it as a fatal error condition and abort in which case systemd would restart it and the service would end up in a good state.

    Below are the relevant logs of a system where this happened:

    Jul 22 13:18:27 usagi systemd[1]: Stopping networking.service - Raise network interfaces...
    Jul 22 13:18:27 usagi kea-dhcp4[3427066]: 2025-07-22 13:18:27.636 ERROR [kea-dhcp4.packets/3427066.139656111945664] DHCP4_BUFFER_RECEIVE_FAIL error on attempt to receive packet: Pkt4FilterLpf to receive UDP4 data
    Jul 22 13:18:28 usagi systemd[1]: networking.service: Deactivated successfully. Jul 22 13:18:28 usagi systemd[1]: Stopped networking.service - Raise network interfaces.
    Jul 22 13:18:28 usagi systemd[1]: networking.service: Consumed 2min 32.148s CPU time, 40.8M memory peak.
    Jul 22 13:18:28 usagi systemd[1]: Starting networking.service - Raise network interfaces...
    Jul 22 13:19:08 usagi systemd[1]: Finished networking.service - Raise network interfaces.

    After that there were no log entries about DHCP requests being received, so the service was not operating.


    -- System Information:
    Debian Release: 13.0
    Architecture: amd64 (x86_64)

    Kernel: Linux 6.12.32-amd64 (SMP w/44 CPU threads; PREEMPT)
    Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
    Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8), LANGUAGE=en_AU:en
    Shell: /bin/sh linked to /usr/bin/dash
    Init: unable to detect

    Versions of packages kea-dhcp4-server depends on:
    ii init-system-helpers 1.68
    ii kea-common 2.6.3-1
    ii libc6 2.41-10
    ii libgcc-s1 14.2.0-19
    ii libstdc++6 14.2.0-19

    kea-dhcp4-server recommends no packages.

    Versions of packages kea-dhcp4-server suggests:
    pn kea-doc <none>

    -- Configuration Files:
    /etc/kea/kea-dhcp4.conf [Errno 13] Permission denied: '/etc/kea/kea-dhcp4.conf'

    -- debconf-show failed

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)