Comment 9 for bug 2050022

I was able to hit the bug after doing another install using "Ubuntu Server (minimized)".

Indeed, the postinst script for ubuntu-advantage-tools seems stuck:

$ ps aux | grep -e dpkg -e apt-get -e advantage

root 932 0.3 2.3 80616 72284 ? S 11:19 0:02 /usr/bin/apt-get --option=Dpkg::Options::=--force-confold --option=Dpkg::options::=--force-unsafe-io --assume-yes --quiet install ubuntu-advantage-tools
root 999 0.0 0.1 8076 4352 pts/0 Ss+ 11:19 0:00 /usr/bin/dpkg --force-confold --force-unsafe-io --status-fd 41 --configure --pending
root 1000 0.0 0.0 2912 1008 pts/0 S+ 11:19 0:00 sh -c (test -x /usr/lib/needrestart/dpkg-status && /usr/lib/needrestart/dpkg-status || cat > /dev/null)
root 1001 0.0 0.0 2912 116 pts/0 S+ 11:19 0:00 sh -c (test -x /usr/lib/needrestart/dpkg-status && /usr/lib/needrestart/dpkg-status || cat > /dev/null)
root 1002 0.0 0.0 2912 980 pts/0 S+ 11:19 0:00 /bin/sh /usr/lib/needrestart/dpkg-status
root 1003 0.0 0.5 19292 16108 pts/0 S+ 11:19 0:00 /usr/bin/perl -w /usr/share/debconf/frontend /var/lib/dpkg/info/ubuntu-advantage-tools.postinst configure
root 1008 0.0 0.0 2912 1836 pts/0 S+ 11:19 0:00 /bin/sh /var/lib/dpkg/info/ubuntu-advantage-tools.postinst configure
root 1225 0.0 0.2 9912 7072 pts/0 S+ 11:19 0:00 /usr/bin/perl /usr/bin/deb-systemd-invoke start ubuntu-advantage.service
root 1229 0.0 0.1 7904 3760 pts/0 S+ 11:19 0:00 systemctl --quiet --system start ubuntu-advantage.service

I also looked to see if the DEBIAN_FRONTEND variable was correctly set but it looks right:

$ strings /proc/1003/environ

DPKG_FRONTEND_LOCKED=true
LD_LIBRARY_PATH=/usr/lib/libeatmydata
DPKG_ROOT=
DPKG_MAINTSCRIPT_DEBUG=0
SYSTEMD_EXEC_PID=684
DPKG_FORCE=security-mac,downgrade,unsafe-io,confold
DPKG_MAINTSCRIPT_ARCH=amd64
DPKG_RUNNING_VERSION=1.21.1
JOURNAL_STREAM=8:20497
DPKG_MAINTSCRIPT_NAME=postinst
TERM=linux
PERL_DL_NONLAZY=1
PATH=/usr/sbin:/usr/bin:/sbin:/bin
INVOCATION_ID=e32e5e41f78b415cb63a7efef6603b7a
LANG=C.UTF-8
LD_PRELOAD=libeatmydata.so
DPKG_MAINTSCRIPT_PACKAGE=ubuntu-advantage-tools
DEBIAN_FRONTEND=noninteractive
DPKG_MAINTSCRIPT_PACKAGE_REFCOUNT=1
DPKG_COLORS=never
PWD=/
DPKG_ADMINDIR=/var/lib/dpkg