Bug#1097699: systemd-resolved defaulting to hostname 'linux' on trixie

[Philip Stewart]

Thanks Luca, but I think it is a missing dependency - I have just
installed libidn2-0 and it's working as expected.

Best,
Phil

On Mon, 17 Feb 2025 at 18:24, Luca Boccassi <bluca at debian.org> wrote:
>
> Control: tags -1 upstream
> Control: close -1
>
> On Mon, 17 Feb 2025 17:47:25 +0000 Philip Stewart
> <philip.stewart.public at gmail.com> wrote:
> > Package: systemd-resolved
> > Version: 257.3-1
> >
> > Hello,
> >
> > On trixie, during the startup of systemd-resolved I observe the info
> > message: "Defaulting to hostname 'linux'."
> >
> > /etc/hostname is populated and the correct hostname is returned by
> > hostnamectl and hostname
> >
> > Attempting to set the hostname (with either hostnamectl or hostname)
> > results in systemd-resolved emitting the warning message: "Failed to
> > determine the local hostname and LLMNR/mDNS names, ignoring: Invalid
> > argument"
> >
> > I prefer to set ReadEtcHosts=no, but observe the behaviour above with
> > ReadEtcHosts set to either yes or no. However, without suitable
> > entries for the local hostname in /etc/hosts, or if ReadEtcHosts=no,
> > systemd-resolved does not synthesize records for the local hostname,
> > and so queries for the local hostname are not found, oddly (to me at
> > least!) causing sudo to emit a warning upon use that it is unable to
> > resolve the host.
> >
> > I do not observe the same behaviour on any of my bookworm machines
> > using systemd-resolved.
>
> There are no patches or specific configuration settings for this, so as
> per the reportbug template please re-run it after setting
> SYSTEMD_LOG_LEVEL=debug in resolved and open a bug upstream on Github
> with the full logs and all the details, and it will be handled:
>
> https://github.com/systemd/systemd/issues/new?template=bug_report.yml