erlexec: cannot execute binary file

If you are building it on your mac, you are most probably building the image for ARM, while your classical server is using x86-64. For cross-compilation I think you need to setup qemu locally.

But I’m creating the release on the same container where I’m trying to run it later, shouldn’t that work?

Can you post your entire Dockerfile?

It doesn’t matter where you create the release, it matters what machine creates the release. You are copying the compiled runtime from your system into the container.

FROM centos:7 as build

SHELL ["/bin/bash", "-c"]

ENV LANG=en_US.UTF-8
# ENV HOME=/opt/build
ENV MIX_ENV prod

# Set the right versions
ENV ERLANG_VERSION latest
ENV ELIXIR_VERSION latest

RUN \
  yum update -y && \
  yum install -y epel-release && \
  yum install -y \
  autoconf \
  curl \
  gcc \
  gcc-c++ \
  git \
  glibc-devel \
  java-1.8.0-openjdk-devel \
  make \
  ncurses-devel \
  openssl-devel \
  unzip \
  wget \
  wxBase.x86_64

RUN git clone https://github.com/asdf-vm/asdf.git ~/.asdf --branch v0.13.1 && \
  echo '. $HOME/.asdf/asdf.sh' >> ~/.bashrc

RUN source ~/.bashrc && \
  asdf plugin add erlang https://github.com/asdf-vm/asdf-erlang.git && \
  asdf plugin add elixir https://github.com/asdf-vm/asdf-elixir.git && \
  asdf install erlang $ERLANG_VERSION && \
  asdf install elixir $ELIXIR_VERSION && \
  asdf global erlang $ERLANG_VERSION && \
  asdf global elixir $ELIXIR_VERSION

# Install build tools
RUN source ~/.bashrc && mix do local.rebar --force, local.hex -if-missing --force

RUN mkdir /app
COPY ./ /app
WORKDIR /app

# Elixir release
RUN source ~/.bashrc && mix do deps.get --only prod, compile, release --overwrite

# Make a release archive
RUN tar -zcvf /app/release.tar.gz -C /app/_build/prod/rel/topo_master .

Even if I do this?

docker build . --file Dockerfile.build --tag topomaster
docker run -it topomaster /app/_build/prod/rel/topo_master/bin/topo_master start

As I understand I’m building the release inside the container, and then trying to run it inside such same container, so it should work unless I’m misunderstanding how docker build works

You want to say that running the docker image on your local machine also doesn’t work?

Sorry… I don’t understand what you mean

OK, that’s a really weird way of installing Erlang and Elixir but there are likely not many officially blessed ways under CentOS – not an expert on it.

Still, I am curious why didn’t you use Hex.PM’s official Docker images?

Have you also tried put CMD /bin/topo_master start at the end of the Dockerfile so you don’t have to get inside it to start the app?

These might not be strongly related to your problem but I’d go through such a laundry list to make sure it’s not something in earlier stages of the deployment decisions.

I tried adding CMD /app/_build/prod/rel/topo_master/bin/topo_master start but I get the same error

Still, I am curious why didn’t you use Hex.PM’s official Docker images?

1. The dedicated servers where we need to deploy the app are running Centos 7 sadly
2. I didn’t know about those images, thanks for sharing