Non-interactive method for dpkg-reconfigure tzdata [closed]

Answer 1

Doing this in a Dockerfile:

FROM ubuntu:xenial

## for apt to be noninteractive
ENV DEBIAN_FRONTEND noninteractive
ENV DEBCONF_NONINTERACTIVE_SEEN true

## preesed tzdata, update package index, upgrade packages and install needed software
RUN truncate -s0 /tmp/preseed.cfg; \
    echo "tzdata tzdata/Areas select Europe" >> /tmp/preseed.cfg; \
    echo "tzdata tzdata/Zones/Europe select Berlin" >> /tmp/preseed.cfg; \
    debconf-set-selections /tmp/preseed.cfg && \
    rm -f /etc/timezone /etc/localtime && \
    apt-get update && \
    apt-get install -y tzdata

## cleanup of files from setup
RUN rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*

In my experiments I determined the removal of the files in /etc necesssary.