Today our routine docker build in our CI got stuck.

Setting up tzdata (2019c-3ubuntu1) ...
debconf: unable to initialize frontend: Dialog
debconf: (TERM is not set, so the dialog frontend is not usable.)
debconf: falling back to frontend: Readline
Configuring tzdata
------------------

Please select the geographic area in which you live. Subsequent configuration
questions will narrow this down by presenting a list of cities, representing
the time zones in which they are located.

  1. Africa      4. Australia  7. Atlantic  10. Pacific  13. Etc
  2. America     5. Arctic     8. EurJob Finished

The base image we used is ubuntu:latest. But Ubuntu just released 20.04 Focal Fossa yesterday, and one of the changes there broke our builds.

Here are 2 options to go around fixing it:

#1 Change to ubuntu:18.04

Just change your base image down to an older stable version.

-FROM ubuntu:latest
+FROM ubuntu:18.04

#2 DEBIAN_FRONTEND=noninteractive apt-get…

-RUN apt-get update && \
+RUN apt-get update && \
+    DEBIAN_FRONTEND=noninteractive \
+    TZ=Asia/Singapore \
     apt-get install -y \

I don’t go for ENV DEBIAN_FRONTEND=noninteractive because that’s not an env var I wanna set permanently for the container image.

Anyway that’s just a quick fix, I hope they patch it soon!

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