4

I try to run a Docker container with the same timezone as my Docker host. The host timezone is CEST.

When I run :

$ date
Thu Apr 16 11:04:11 CEST 2020
$ docker run -e TZ=CEST debian:buster date
Thu Apr 16 09:04:14 CEST 2020

The container is 2 hours behind the host.

On the other hand, if I set TZ=Europe/Paris, it works as expected :

$ docker run -e TZ=Europe/Paris debian:buster date
Thu Apr 16 11:04:22 CEST 2020

Is this a bug or am I missing something?

4

The timezone is set by default and you need to change it manually.

There are some options:

Set it in the Dockerfile:

ENV TZ=America/Los_Angeles
RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone

Using volumes to synchronize with your host:

volumes:
- "/etc/timezone:/etc/timezone:ro"
- "/etc/localtime:/etc/localtime:ro"

or

docker run -v /etc/timezone:/etc/timezone:ro

Finally, set it manually but if you restart the container you lose the configuration:

docker run -e TZ=America/New_York ubuntu date
2
  • This doesn't answer the question. As you can see, I'm already using TZ environment variable to set the timezone. But in the case of TZ=CEST, which is the timezone configured on the host, it has unexpected behavior. Apr 16 '20 at 12:22
  • Sorry for the misunderstood. If you try to configure the TZ with tzselect you can not use CEST. So As far I can see there is no possible to use TZ=CEST in Debian 10 to set the TZ. You need to use 'Europe/Madrid' or similar.
    – ginerama
    Apr 16 '20 at 13:07
1

After some research, it appears that CEST is not a valid value for TZ environment variable. CEST is just a displayable version of CET when the current date is summer.

In fact, if I set TZ to an obviously invalid value, it gives :

$ TZ=FOO date
Fri Apr 17 14:07:56 FOO 2020

Also note that it has nothing to do with Docker.

References :

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.