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CernVM File System (CVMFS)

What is CVMFS?

The CernVM File System ("CernVM-FS" or "CVMFS") is a tool that allows for efficient global distribution of software and data that does not change frequently. Its name indicates its origins for use by virtual machines in use by the high energy physics community, however, it has wider applicability and usage. It caches files to disk so that, after the initial download, file access for the client is speedy.

Within IGWN, CVMFS is being used to distribute both instrument data ("frame files") and analysis software for use at the shared computing centres and by distributed workflows. You may elect to install CVMFS on your workstation for ease of access to recent data and software.

No authenticated data access on macOS

The MacOS CVMFS client cannot yet access LIGO instrument data, though it is hoped that that feature will be developed.

Installing the CVMFS client

  1. Configure the necessary extra Apt repository for CERN-maintained CVMFS using these instructions

  2. Configure the necessary extra Apt repository for cvmfs-contrib using these instructions.

  3. Update and install the relevant packages:

    sudo apt-get update
    sudo apt-get install cvmfs cvmfs-config-osg
    
  4. Run a basic setup:

    sudo cvmfs_config setup
    
  5. Create a default.local configuration for CVMFS that references the repositories you care about:

    sudo bash -c 'cat > /etc/cvmfs/default.local' << EOF
    CVMFS_REPOSITORIES=cms.cern.ch,oasis.opensciencegrid.org
    CVMFS_QUOTA_LIMIT=20000
    CVMFS_HTTP_PROXY=DIRECT
    EOF
    
  6. Verify the file system:

    cvmfs_config probe
    

In construction

Instructions for macOS have not been tested yet!

In construction

Instructions for RHEL have not been tested yet!