I want to install certbot in a docker environment with an Ubuntu 16.04 image:

For example:

docker run -it ubuntu:16.04 /bin/bash

When I'm inside the container, the most straightforward way to install certbot does not work as it requires user intervention:

apt-get update && 

apt-get install -y software-properties-common && 

add-apt-repository -y -u ppa:certbot/certbot && 

apt-get install -y certbot

The problem is tzdata, which stops with this interactive dialog:

Extracting templates from packages: 100%

Preconfiguring packages ...

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. Europe    11. SystemV

 3. Antarctica  6. Asia       9. Indian    12. US

Geographic area: 

Strangely enough, it works when I install tzdata before adding the ppa:

apt-get update && 

apt-get install -y tzdata && 

apt-get install -y software-properties-common && 

add-apt-repository -y -u ppa:certbot/certbot && 

apt-get install -y certbot

Questions:

• Why makes it a difference whether I install tzdata before or after adding the ppa?


• Is there a better approach for avoiding the interactive dialog when installing certbot?