Set timezone in your docker image

TL;DR

RUN apt update && apt install tzdata -y
ENV TZ="America/New_York"

Debian

When your image is based on Debian, or your image's root is based on Debian, you can use ENV TZ in Dockerfile:

FROM debian:10

ENV TZ="America/New_York"

Ubuntu

When your image/root-image is based on Ubuntu, use:

RUN apt-get update && \
    apt-get install -yq tzdata && \
    ln -fs /usr/share/zoneinfo/America/New_York /etc/localtime && \
    dpkg-reconfigure -f noninteractive tzdata

If you don't know what your base image is, you could try putting both:

RUN apt-get update && \
    apt-get install -yq tzdata && \
    ln -fs /usr/share/zoneinfo/America/New_York /etc/localtime && \
    dpkg-reconfigure -f noninteractive tzdata

ENV TZ="America/New_York"

Also quote from and credits to @peter279k in the comment below:

If using the ENV to set TZ to set the timezone, it should have the tzdata package installed on Linux distribution Docker base image.
After investigating some common Linux distributions, the Debian and CentOS have the tzdata installed on their Base Docker images.
And Ubuntu doesn't have the tzdata package on the Docker base image.

So another solution is:

RUN apt update && apt install tzdata -y
ENV TZ="America/New_York"

Comments

[peter279k]

To set correct system timezone on Ubuntu 18.04 or 20.04 base image, it should use following Dockerfile:

FROM ubuntu:18.04

RUN apt-get update && \
    apt-get install -yq tzdata && \
    ln -fs /usr/share/zoneinfo/Asia/Taipei /etc/localtime && \
    dpkg-reconfigure -f noninteractive tzdata

FROM ubuntu:20.04

RUN apt-get update && \
    apt-get install -yq tzdata && \
    ln -fs /usr/share/zoneinfo/Asia/Taipei /etc/localtime && \
    dpkg-reconfigure -f noninteractive tzdata

[BC]

Thank you, Peter. Question though, if the one line set env TZ works, what’s the benefits of using your long version ?

[peter279k]

Setting ENV TZ cannot be worked for setting system timezone.

For example, using the following Dockefile:

FROM ubuntu:20.04

ENV TZ="Asia/Taipei"

When building above Docker image is done, running this image as container with interactive pseudo terminal:

lee@lee-VirtualBox:~/test$ docker run -it test_timezone:latest bash
root@b16f08e2d542:/#
root@b16f08e2d542:/# date
Sat Aug 14 03:18:44 Asia 2021

The timezone is correct, but current time is incorrect.

Then using the following Dockerfile and build them to be the Docker image:

FROM ubuntu:20.04

RUN apt-get update && \
    apt-get install -yq tzdata && \
    ln -fs /usr/share/zoneinfo/Asia/Taipei /etc/localtime && \
    dpkg-reconfigure -f noninteractive tzdata

After building above Docker image is done, running this as a container with interactive pseudo terminal:

lee@lee-VirtualBox:~/test$ docker run -it test_timezone:tzdata bash
root@9f778cfd6e1a:/# date
Sat Aug 14 11:23:09 CST 2021
root@9f778cfd6e1a:/#

[BC]

Ah, interesting, thank you. When I was using the "ENV TZ" method, my base image is FROM node:16-slim, and it worked perfectly when run date:

Fri Aug 13 23:47:09 EDT 2021

Do you know why that works while FROM ubuntu:20.04 does not? Is it b/c the node:16 image already set the tzdata like you did?

[peter279k]

The node:16-slim is based on Debian:10 image to build the Node.js version 16 environment.

And it's worked for Debian 10 when setting the ENV TZ to set the timezone.

I think setting ENV TZ is not the common way to set system timezone on every Linux distributions.

[BC]

Hmm, you are right, just tried FROM debian:10 , the ENV TZ way works. Seems just not working for ubuntu. Thank you for pointing out. TIL.

[peter279k]

If using the ENV to set TZ to set the timezone, it should have the tzdata package installed on Linux distribution Docker base image.

After investigating some common Linux distributions, the Debian and CentOS have the tzdata installed on their Base Docker images.

And Ubuntu doesn't have the tzdata package on the Docker base image.

[peter279k]

That's the reason why I need to use apt-get update and apt-get install -yq tzdata firstly on my Dockerfile when using the Ubuntu 20.04 for my Docker base image.

Of course, we can simplify my Dockerfile when using the Ubuntu to be the Docker base image:

FROM ubuntu:20.04

RUN apt-get update && \
    apt-get install -yq tzdata

ENV TZ="Asia/Taipei"

[BC]

Got it, thanks for the awesome explanation. 👍

[Brent Groves]

For ubuntu 22.04 I suggest blog.game-changing.de/how-to-set-t...
The author explains the details but the gist is to include the following in your dockerfile.

FROM ubuntu:22.04

ARG DEBIAN_FRONTEND=noninteractive

ENV TZ Europe/Berlin

RUN apt-get update \
&& apt-get install -yq tzdata locales \
&& rm -rf /var/lib/apt/lists/* \

&& sed -i '/en_US.UTF-8/s/^# //g' /etc/locale.gen \
&& locale-gen \
&& ln -fs /usr/share/zoneinfo/${TZ} /etc/localtime \
&& dpkg-reconfigure tzdata

ENV LANG en_US.UTF-8

ENV LANGUAGE en_US:en
ENV LC_ALL en_US.UTF-8

CMD ["/bin/bash"]

[KavinduGeesara]

Could you please tell me how to set on alpine base image?

my dockerfile is like this:

FROM alpine
ENV TZ="Asia/Colombo"

[BC]

I think you need to install the tzdata first before setting the TZ, like ubuntu:

FROM alpine:latest

RUN apk update && apk add tzdata
ENV TZ="America/New_York"

This works for me.