SingularityCE 4.1.0

[dtrudg]

SingularityCE 4.1.0 is the first release in the 4.1 series, introducing Dockerfile builds, multi-layer OCI-SIF images, and many other improvements. See the release notes below, and the user and admin guides for more information:

• https://docs.sylabs.io/guides/4.1/admin-guide/new.html
• https://docs.sylabs.io/guides/4.1/user-guide/new.html

Changed defaults / behaviours

• --oci mode containers and native mode instances can now be successfully started as a non-root user on cgroups v2 systems when both:

  • The system configuration / environment does not provide the correct information necessary to communicate with systemd via dbus.
  • Resource limits (e.g. --cpus) have not been requested.

  The container / instance will be started in the current cgroup, and information about the configuration issue displayed to the user as warnings.

• In native mode, SIF/SquashFS container images will now be mounted with squashfuse when kernel mounts are disabled in singularity.conf, or cannot be used (non-setuid / user namespace workflow). If the FUSE mount fails, Singularity will fall back to extracting the container to a temporary sandbox in order to run it.

• In native mode, bare extfs container images will now be mounted with fuse2fs when kernel mounts are disabled in singularity.conf, or cannot be used (non-setuid / user namespace workflow).

New Features & Functionality

• The registry login and registry logout commands now support a --authfile <path> flag, which causes the OCI credentials to be written to / removed from a custom file located at <path> instead of the default location ($HOME/.singularity/docker-config.json). The commands pull, push, run, exec, shell, and instance start can now also be passed a --authfile <path> option, to read OCI registry credentials from this custom file.
• A new --keep-layers flag, for the pull and run/shell/exec/instance startcommands, allows individual layers to be preserved when an OCI-SIF image is created from an OCI source. Multi layer OCI-SIF images can be run with SingularityCE 4.1 and later.
• Singularity will now build OCI-SIF images from Dockerfiles, if the --oci flag is used with the build command. Provide a Dockerfile as the final argument to build, instead of a Singularity definition (.def) file. Supports --build-arg / --build-arg-file options, --arch for cross-architecture builds, --authfile and other authentication options, and more. See the user guide for more information.
• Docker-style SCIF containers (https://sci-f.github.io/tutorial-preview-install) are now supported. If the entrypoint of an OCI container is the scif executable, then the run / exec / shell commands in --oci mode can be given the --app <appname> flag, and will automatically invoke the relevant SCIF command.
• A new --tmp-sandbox flag has been added to the run / shell / exec / instance start commands. This will force Singularity to extract a container to a temporary sandbox before running it, when it would otherwise perform a kernel or FUSE mount.

Bug Fixes

• Added missing tmp sandbox directive to singularity.conf template.

Deprecated Functionality

• The experimental --sif-fuse flag, and sif fuse directive in singularity.conf are deprecated. The flag and directive were used to enable experimental mounting of SIF/SquashFS container images with FUSE in prior versions of Singularity. From 4.1, FUSE mounts are used automatically when kernel mounts are disabled / not available.

Thanks / Reporting Bugs

Thanks to our contributors for code, feedback and, testing efforts!

As always, please report any bugs to: https://github.com/sylabs/singularity/issues/new

If you think that you've discovered a security vulnerability please report it to: security@sylabs.io

Have fun!

Downloads

Source Code

Please use the singularity-ce-4.1.0.tar.gz download below to obtain and install SingularityCE 4.1.0. The GitHub auto-generated 'Source Code' downloads do not include required dependencies etc.

Packages

RPM / DEB packages are provided for:

• Ubuntu 20.04 (focal)
• Ubuntu 22.04 (jammy)
• RHEL/CentOS 7 (el7)
• RHEL/CentOS/AlmaLinux/Rocky 8 (el8)
• RHEL/CentOS/AlmaLinux/Rocky 9 (el9)

These packages were built with Go 1.21.6

---

This discussion was created from the release SingularityCE 4.1.0.