Apptainer / Singularity

In this article, (1) we first introduce the intra-node communication issue with MPI applications and Apptainer without setuid (default version of Apptainer v1.1.x and v1.2.x) that uses unprivileged user namespace that happens with certain types of intra-node communication transport. (2) We show you test results of various MPIs, communication frameworks, interconnects, and intra-node communication transports....

In a previous article, I demonstrated how Warewulf makes it simple to deploy an HPC cluster. Now, I don’t know about you; but, once I have a cluster, I immediately start looking for something to run on it. But I’m a systems guy—not a domain scientist—so that usually means I start benchmarking. Recently at CIQ,...

In our previous blog post, OpenFOAM Supports Apptainer v1.2.0 Template Definition File Feature, I showed you how to use OpenFOAM (R) (OpenCFD Ltd.) with Apptainer; and in A New Approach to MPI in Apptainer, I demonstrated how to build and run a a portable MPI container with Apptainer's “Fully Containerized Model”solution. In this article, I...

Introduction We are happy to announce that OpenFOAM® (OpenCFD Ltd.) is the very first project that officially supports the brand-new Apptainer v1.2.0 feature “template definition file” just released on July 18, 2023. OpenFOAM officially supports Apptainer since OpenFOAM v2212 and since then we have closely worked together on the OpenFOAM container repository. In this blog...

As a follow-up to CIQ’s “Cloud Day with Apptainer” webinar, here’s more information about how to utilize Apptainers with the container/artifact registry offerings around the public cloud space. Apptainer uses the Singularity Image Format (SIF) for its containers, which are supported in many container/artifacts registries through the use of the “OCI Registries As Storage” (ORAS)...

While Apptainer has always supported MPI-enabled applications, it can be tricky to get them working. In this blog post, we’ll detail the “wire-up“ problem that often plagues MPI in containers, traditional approaches and their shortcomings, and provide a new approach that allows you to run completely containerized MPI! The work detailed here has been presented...

Apptainer is the most popular container solution for HPC. It has great integration with common specialized HPC hardware/software like GPU devices and MPI software stacks, and the containerized model it brings adds security and reproducibility that makes it ideal for deployment in a multi-user HPC cluster environment. One major use case for Apptainer is in...

It has been awhile since Singularity became Apptainer. If you haven't updated Singularity to Apptainer, or if you accidentally switched to SingularityCE and now want to switch back, this post is for you! How Singularity became Apptainer In May 2021, a private company wanted to develop their own version of Singularity autonomously.  It created a fork...

Apptainer is the most popular container solution for HPC. It has great integration with common specialized HPC hardware/software like GPU devices and MPI software stacks, and the containerized model it brings adds security and reproducibility that make it ideal for deployment in a multi-user HPC cluster environment. One major use case for Apptainer is in...

Apptainer is often compared to Docker as both a container runtime engine and container management environment. In general, each tool targets a different use case; but the two projects notably differ in their runtime strategy. In general, Docker is designed to host system services, and Apptainer is designed to containerize end-user applications (often in a...

It is possible to configure your environment to start Apptainer (with arbitrary commands and options/arguments) in a Delve debugging session and then attach to the running server with VSCode.  This gives you the ability to set break points, step in/out/over lines of code and functions, interrogate variables during runtime, etc.  But it’s a little tricky...