Image Compatibility In Cloud Native Environments

Image Compatibility In Cloud Native Environments The need for image compatibility specification Dependencies between containers and host OS Multi-cloud and hybrid cloud challenges Image compatibility initiative Implementation in Node Feature Discovery Compatibility specification Client implementation for node validation Examples of usage Conclusion Get involved In industries where systems must run very reliably and meet strict performance criteria such as telecommunication, high-performance or AI computing, containerized applications often need specific operating system configuration or hardware presence. It is common practice to require the use of specific versions of the kernel, its configuration, device drivers, or system components. Despite the existence of the Open Container Initiative (OCI) , a governing community to define standards and specifications for container images, there has been a gap in expression of such compatibility requirements. The need to address this issue has led to different proposals and, ultimately, an implementation in Kubernetes' Node Feature Discovery (NFD). NFD is an open source Kubernetes project that automatically detects and reports hardware and system features of cluster nodes. This information helps users to schedule workloads on nodes that meet specific system requirements, which is especially useful for applications with strict hardware or operating system dependencies. A container image is built on a base image, which provides a minimal runtime environment, often a stripped-down Linux userland, completely empty or distroless. When an application requires certain features from the host OS, compatibility issues arise. These dependencies can manifest in several ways: Drivers : Host driver versions must match the supported range of a library version inside the container to avoid compatibility problems. Examples include GPUs and network drivers. Libraries or Software : The container must come with a specific version or range of versions for a library or software to run optimally in the environment. Examples from high performance computing are MPI, EFA, or Infiniband.