You cannot save a variable for later use in other Dockerfile commands (if that is your intention). This is because each RUN happens in a new shell. However, if you just want to capture the output of ls you should be able to do it in one RUN compound command. For example: RUN file=”$(ls -1 … Read more
The VOLUME command will specify a mount point in the container. This mount point will be mapped to a location on the host that is either specified when the container is created or (when not specified) chosen automatically from a directory created in /var/lib/docker/volumes. If the directory chosen as the mount point contains any files … Read more
first of all, you don’t want to install the “snap” package, as it is not related to “snapd”. Secondly, myself stumbled across this issue of installing snapd within a docker container: TLDR; Running snapd that way is currently not supported. But that question has been asked already at the snapcraft forums. One of snapd’s dependencies … Read more
The right way to do it is deleting cmd [“…”] docker run –name test test/test-backend /srv/www/bin/gunicorn.sh
The Dockerfile is for creating images not containers. You can now give names to your containers using the new –name flag for docker run. If –name is not provided Docker will automatically generate an alphanumeric string for the container name.
Each Dockerfile RUN step runs a new container and a new shell. If you try to set an environment variable in one shell, it will not be visible later on. For example, you might experiment with this Dockerfile: FROM busybox ENV FOO=foo1 RUN export FOO=foo2 RUN export BAR=bar CMD echo FOO is $FOO, BAR is … Read more
A little late but you could also use build args and change your code to: FROM python:3.6.5-stretch [ … ] ARG MY_SERVICE_PORT=8080 ARG MY_SERVICE_PORT_RPC=50051 # 8080 and 50051 would be the defaults [ … ] # Still functions like environment variables 🙂 EXPOSE ${MY_SERVICE_PORT} EXPOSE ${MY_SERVICE_PORT_RPC} Then you can build with docker build –build-arg MY_SERVICE_PORT=80 … Read more
Yes, it is somewhat vague in docker 20.10.5. Could use a pull request or two to update documentation. The docker driver cache uses the same storage driver as used for image layers. Metadata is stored in databases at /var/lib/docker/buildkit. When docker uses overlay2 storage driver, the layer is in /var/lib/docker/overlay2/<ID>/diff/. For <ID>, see below. /var/lib/docker … Read more
You need to install the tzdata package and then set the enviroment variable TZ to a timezone. (List with all the timezones) FROM alpine:latest RUN apk add –no-cache tzdata ENV TZ=Europe/Copenhagen Output $ docker run –rm alpine date Tue Aug 31 09:52:08 UTC 2021 $ docker run –rm myimage date Tue Aug 31 11:52:13 CEST … Read more
I had the same issue in Dockerfile, then I used ARG DEBIAN_FRONTEND=noninteractive after base image and it works for me: Example Dockerfile: FROM ubuntu ARG DEBIAN_FRONTEND=noninteractive