Check or Change the Timezone in Debian

To see or change what timezone your Debian system is configured for:

dpkg-reconfigure tzdata

More detailed information is available in the Debian Wiki

More specifically, I used this in a setup of HypriotOS, a minimal Debian-based operating systems that is optimised to run Docker on ARM devices. In this instance it was an old Raspberry Pi Model B running NodeRed in a Docker Container.

I needed to get the time in the Docker Container to match the time on the host. Achieved, as below, where /etc/localtime on the host is mapped to /etc/localtime in the container when it is created.

docker run --restart=always \
           -p 1880:1880 \
           -d \
           --name nodered \
           -v /etc/localtime:/etc/localtime:ro \
           -v node_red_user_data:/data \
           nodered/node-red-docker:0.17.4-rpi