Installation of resolvconf fails for Trixie running in a Docker
container. Sample session:


% docker run -it --rm debian:13
Unable to find image 'debian:13' locally
13: Pulling from library/debian
80b7316254b3: Pull complete
Digest: sha256:6d87375016340817ac2391e670971725a9981cfc24e221c47734681ed0f6c0f5
Status: Downloaded newer image for debian:13
root@783aed9ca14d:/# apt update
Get:1 http://deb.debian.org/debian trixie InRelease [138 kB]
Get:2 http://deb.debian.org/debian trixie-updates InRelease [47.1 kB]
Get:3 http://deb.debian.org/debian-security trixie-security InRelease [43.4 kB]
Get:4 http://deb.debian.org/debian trixie/main amd64 Packages [9668 kB]
Get:5 http://deb.debian.org/debian trixie-updates/main amd64 Packages [2432 B]
Get:6 http://deb.debian.org/debian-security trixie-security/main amd64 Packages [20.5 kB]
Fetched 9919 kB in 1s (14.7 MB/s)
All packages are up to date.
root@783aed9ca14d:/# apt install resolvconf
Installing:
  resolvconf

Summary:
  Upgrading: 0, Installing: 1, Removing: 0, Not Upgrading: 0
  Download size: 57.1 kB
  Space needed: 190 kB / 366 GB available

Get:1 http://deb.debian.org/debian trixie/main amd64 resolvconf all 1.94 [57.1 kB]
Fetched 57.1 kB in 0s (2332 kB/s)
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 79, <STDIN> line 1.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC entries checked: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.40.1 /usr/local/share/perl/5.40.1 /usr/lib/x86_64-linux-gnu/perl5/5.40 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl-base /usr/lib/x86_64-linux-gnu/perl/5.40 /usr/share/perl/5.40 /usr/local/lib/site_perl) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 8, <STDIN> line 1.)
debconf: falling back to frontend: Teletype
Preconfiguring packages ...
Selecting previously unselected package resolvconf.
(Reading database ... 4934 files and directories currently installed.)
Preparing to unpack .../resolvconf_1.94_all.deb ...
Unpacking resolvconf (1.94) ...
Setting up resolvconf (1.94) ...
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 79.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC entries checked: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.40.1 /usr/local/share/perl/5.40.1 /usr/lib/x86_64-linux-gnu/perl5/5.40 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl-base /usr/lib/x86_64-linux-gnu/perl/5.40 /usr/share/perl/5.40 /usr/local/lib/site_perl) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 8.)
debconf: falling back to frontend: Teletype
ln: failed to create symbolic link '/etc/resolv.conf': Device or resource busy
dpkg: error processing package resolvconf (--configure):
 installed resolvconf package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
 resolvconf
Error: Sub-process /usr/bin/dpkg returned an error code (1)


In real life I would have never tried to install resolvconf on purpose
in a Docker container, but it popped up in a dependency chain. I can't
help it. IMHO it would be sufficient if resolvconf.postinst just shows
a warning.


Regards

Harri