epics-containers

The goal of this project is to provide multiple EPICS docker containers for development and testing (those can also be used for training).

All containers can be found here: https://hub.docker.com/repository/docker/stephanecea/epics.

Related projects

• https://epics-containers.github.io/main/index.html
• https://github.com/pklaus/docker-epics-directory
• https://github.com/prjemian/epics-docker

Multi-Arch prerequisites

⚠️ Prerequisite(s) ⚠️: if you intend to build and/or run linux/arm64 or linux/ppc64le on your amd64 host, then you will need to install and configure binfmt and qemu like describe bellow. If not, then you can skip this section.

E.g. on Ubuntu, install qemu binfmt-support and qemu-user-static:

$ sudo apt install qemu binfmt-support qemu-user-static

E.g. on Arch Linux, install qemu-headless binfmt-qemu-static and qemu-user-static-bin:

$ sudo pacman -S qemu-headless

$ git clone https://aur.archlinux.org/binfmt-qemu-static.git
$ cd binfmt-qemu-static
$ makepkg -si
$ cd ..

$ git clone https://aur.archlinux.org/packages/qemu-user-static-bin
$ cd qemu-user-static-bin
$ makepkg -si
$ cd ..

Then register additional architectures and test the arm64 one:

$ docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
$ docker run --rm -t arm64v8/ubuntu uname -m # Testing the emulation environment

How to use

⚠️ Prerequisite(s) ⚠️: docker

• Explore and use an EPICS container in an interactive bash shell:

  $ docker pull stephanecea/epics:rockylinux-8-epics-7.0.6.1-synapps-6.2.1
  $ docker run -it stephanecea/epics:rockylinux-8-epics-7.0.6.1-synapps-6.2.1 bash

• Create an EPICS top on your host computer and test it in an EPICS container, e.g. test the default EPICS example template top against EPICS base R7.0.1:

  $ cd /path/to/example-top
  $ makeBaseApp.pl -a linux-x86_64 -t example example
  $ makeBaseApp.pl -a linux-x86_64 -i -t example -p example example
  $ make clean && make
  
  $ vi confiure/RELEASE
      > ...
    ~ > EPICS_BASE = /path/to/your/epics/base
      > ...
  
  $ chmod +x iocBoot/iocexample/st.cmd
  $ cd iocBoot/iocexample/st.cmd
  $ ./st.cmd
      epics> echo "check your things here"
      epics> exit
  
  $ docker pull stephanecea/epics:rockylinux-8-epics-7.0.6.1-synapps-6.2.1
  $ id # find your user ID and group ID in order to run your container with it
      > uid=1234(username) gid=1234(username) ...
  
  $ docker run -it --user 1000:1000 -v "/path/to/example-top:/opt/epics/example-top" stephanecea/epics:rockylinux-8-epics-7.0.6.1 bash
  
      container$ cd /opt/epics/example-top
      container$ vi confiure/RELEASE
          > ...
        ~ > EPICS_BASE = /opt/epics/base
          > ...
      conainer$ make clean && make
  
      container$ cd iocBoot/iocexample/st.cmd
      container$ ./st.cmd
          epics> echo "check your things here"
          epics> exit
  
      container$ exit
  
  $ docker run -it --user 1000:1000 -v "/path/to/example-top:/opt/epics/example-top" stephanecea/epics:rockylinux-8-epics-7.0.6.1 ./opt/epics/example-top/run_your_ci_test_script.sh

• Run an example top from, e.g. the example top build against EPICS R7.0.6.1:

  $ docker pull stephanecea/epics:rockylinux-8-epics-7.0.6.1-example-top
  $ docker run -it --user 1000:1000 stephanecea/epics:rockylinux-8-epics-7.0.6.1-example-top bash -c "cd /opt/epics/example-top/iocBoot/iocexample && ./st.cmd"

• Run an arm64 container on a amd64 host:

  • ⚠️ Prerequisite(s) ⚠️: multi-arch prerequisites
  • E.g. pull the epics:centos-7-epics-7.0.6.1 arm64 container and run it:

    $ docker pull --platform=linux/arm64 stephanecea/epics:centos-7-epics-7.0.6.1
    $ docker run -it --platform=linux/arm64 stephanecea/epics:centos-7-epics-7.0.6.1 bash

How to build

⚠️ Prerequisite(s) ⚠️: Multi-Arch prerequisites

• First, create a builder in order to access new multi-architecture features:

  $ docker buildx ls
  $ docker buildx create --name mybuilder
  $ docker buildx use mybuilder
  $ docker buildx inspect --bootstrap

• Now build the image you want, e.g. epics:centos-7-epics-7.0.6.1 for both linux/amd64 and linux/arm64:

  $ docker buildx build --platform=linux/amd64,linux/arm64 -t stephanecea/epics:centos-7-epics-7.0.6.1 epics/centos-7-epics-7.0.6.1

• If you want to decrease the size of the images you build, you can use the new squash docker option:

  • In order to do so, you have to activate the experimental features of docker, by creating the file /etc/docker/daemon.json with the following content:

    {"experimental":true}

    Then restart docker and check that experimental features are enabled:

    $ sudo systemctl restart docker
    $ docker version | grep -i experimental

  • Now you can build the image you want, e.g. epics:centos-7-epics-7.0.6.1 for both linux/amd64 and linux/arm64, with the --squash option:

    $ docker buildx build --squash --platform=linux/amd64,linux/arm64 -t stephanecea/epics:centos-7-epics-7.0.6.1 epics/centos-7-epics-7.0.6.1

Build troubleshooting

docker: 'buildx' is not a docker command. error

If you get following error:

docker: 'buildx' is not a docker command.
See 'docker --help'

Even after following those instructions: https://medium.com/@artur.klauser/building-multi-architecture-docker-images-with-buildx-27d80f7e2408

Then you can install buildx manually like described here: https://github.com/docker/buildx#manual-download

Useful build references

• https://www.reddit.com/r/docker/comments/c75uhq/how_to_run_arm64_containers_from_amd64_hosts_and/
• https://matchboxdorry.gitbooks.io/matchboxblog/content/blogs/build_and_run_arm_images.html
• https://www.stereolabs.com/docs/docker/building-arm-container-on-x86/
• https://docs.docker.com/desktop/multi-arch/
• https://medium.com/@artur.klauser/building-multi-architecture-docker-images-with-buildx-27d80f7e2408