Containers

Apptainer (formerly Singularity) is a container solution for scientific and application-driven workloads. See the Apptainer User Guide for details.

Build an Apptainer Container

Note

Admin assistance required

Apptainer requires fakeroot privilege for non-root users to create container images. Please contact an HAL admin or submit a support request to set up your account with fakeroot.

Build a container from an Apptainer recipe (ubuntu1604-cuda92-ompi400.def):

wget https://wiki.ncsa.illinois.edu/download/attachments/82518873 ubuntu1604-cuda92-ompi400.def
apptainer build ubuntu1604-cuda92-ompi400.sif ubuntu1604-cuda92-ompi400.def

Pull a container from Apptainer Hub or Docker Hub:

apptainer pull docker://nvidia/cuda-ppc64le:9.2-cudnn7-devel-ubuntu16.04

Run an Apptainer Container

Warning

Unlike Docker (which provides an isolated filesystem), Singularity mounts your home directory into the container. Be aware of this so you don’t accidentally delete things in your home directory.

Run a container with exec command:

bashmpirun -n 4 apptainer exec --nv /opt/apps/samples-image/ubuntu1604-cuda92-ompi400.sif hostname

Run a container with shell:

bashapptainer shell --nv /opt/apps/samples-image/ubuntu1604-cuda92-ompi400.sif

Build a Writable Apptainer Container

By default, the Apptainer container filesystem is read-only. There are 2 options to build a writable Apptainer container.

`--sandbox`

The --sandbox option allows users to create a container within a writable directory (a sandbox). It’s possible to create a sandbox without root privileges, but to ensure proper file permissions it is recommended to do so as root.

apptainer build --sandbox cuda-ppc64le/ docker://nvidia/cuda-ppc64le:9.2-cudnn7-devel-ubuntu16.0
apptainer shell --writable cuda-ppc64le/

`--writable`

The --writable option allows users to create a writable ext3 image. Root privileges are required to create writable containers.

apptainer build --writable cuda-ppc64le.sif docker://nvidia/cuda-ppc64le:9.2-cudnn7-devel-ubuntu16.04
apptainer shell --writable cuda-ppc64le.sif

Build a Writable Apptainer Container Based on an Existing Read-Only Image

Convert it to a writable directory (a sandbox):

apptainer build --sandbox cuda-ppc64le-mod/ cuda-ppc64le.sif
apptainer shell --writable cuda-ppc64le-mod/

Use an existing container as a target to build a new container

apptainer build --writable cuda-ppc64le-mod.sif cuda-ppc64le.sif
apptainer shell --writable cuda-ppc64le-mod.sif

Run a Container with an x86 Architecture Image on an IBM ppc64le System

Apptainer cannot directly run x86 binaries on an IBM Power system because the bytes of machine code are different. You need to make sure your images are built for ppc64le rather than x86.

`--nv` Option

The --nv option allows the Apptainer container to leverage the NVIDIA GPU on the host system. Use this option if the container asks for nvidia-docker support.