CernVM 5

• About CernVM 5
  • CernVM-FS
  • Host integration
• Building the image
  • With Docker
  • With Buildah
• Pulling from CERN Harbor
  • Deriving from the image
• Running the image as a container
  • Using Docker
  • Using Podman
  • Using Singularity and unpacked.cern.ch

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About CernVM 5

This repository contains the source code and build scripts for the EL8-based CernVM 5 container image. The image is intended to be a JeOS (Just enough OS) and provides:

• A CernVM File System client with its minimal dependencies
• The HEP_OSlibs meta package

CernVM-FS

For most Use Cases it is sensible to run the image with CernVM-FS either mounted from the host or from the inside of the container.

• The repository cernvm-five.cern.ch provides common System Applications like editors, browsers or cloud tools.
• Other repositories with Scientific Applications can be mounted as usual.

NOTE: System Applications don't use LD_LIBRARY_PATH and therefore can be run in parallel to other applications from other repositories safely.

Host integration

Besides /cvmfs the image comes with two more dedicated host mount points:

• /workspace as a shared folder between container and host
• /data for data integration with for e.g. EOS

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Building the image

With Docker

docker build -f docker/Dockerfile . -t cernvm-five

With Buildah in for e.g., in a build container

buildah bud -t cernvm-five -f docker/Dockerfile .  

Pulling from CERN Harbor

docker pull registry.cern.ch/cernvm/five/cernvm-five:latest

Deriving from the image

CernVM 5 can serve as a base layer for custom container images. For e.g. use

FROM registry.cern.ch/cernvm/five/cernvm-five:latest
RUN dnf -y install mypackage
COPY /my_init.sh / 
ENTRYPOINT ["bash", "/my_init.sh"]

to extend the image as you wish.

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Running the image as a container

Make sure to use the dedicated mountpoints for host integration. It is recommended to run the image with either CernVM-FS mounted from the host or with an independent CernVM-FS client inside the container

Using Docker

docker run -it -v /cvmfs:/cvmfs:ro registry.cern.ch/cernvm/five/cernvm-five:latest bash

docker run -it --device /dev/fuse --cap-add SYS_ADMIN registry.cern.ch/cernvm/five/cernvm-five:latest bash

Using Podman

podman run -it -v /cvmfs:/cvmfs:ro registry.cern.ch/cernvm/five/cernvm-five:latest bash

podman run -it --device /dev/fuse --cap-add SYS_ADMIN registry.cern.ch/cernvm/five/cernvm-five:latest bash

Using Singularity and unpacked.cern.ch

singularity shell /cvmfs/unpacked.cern.ch/registry.cern.ch/cernvm/five/cernvm-five\:latest/