Kubernetes 1.24 officially deprecated Dockershim in favor of containerd, explaining the reasons, the underlying container runtime components, the changes in pod creation workflow, the impact on users and operators, and providing practical migration steps and best‑practice recommendations.
Starting with Kubernetes v1.24 the built‑in dockershim is removed, requiring users to switch to a CRI‑compatible runtime such as containerd or CRI‑O—or install cri‑dockerd for Docker compatibility—while updating scripts, logs, and tooling, and using crictl or ctr for debugging and managing containers and pods.
This article provides a detailed analysis of the kubelet CRI pod creation workflow, using the dockershim implementation as an example, and includes step‑by‑step code walkthroughs of SyncPod, sandbox creation, and the interactions between kubelet, CRI shim, Docker, and CNI.
The article explains the history of containers, the role of Docker and Kubernetes, why Kubernetes is deprecating Docker's dockershim, the timeline for the change, its impact on users, and the steps required to migrate to OCI‑compatible runtimes such as containerd or CRI‑O.
This article explains the rationale behind Kubernetes' decision to remove Dockershim, outlines the role of the Container Runtime Interface (CRI), compares Docker's feature set with CRI requirements, and discusses the impact on extensibility and future container runtimes.
This article explains why the Kubernetes dockershim component is being phased out, compares Docker and containerd command usage, and provides a step‑by‑step guide to set up a Kubernetes 1.20.5 cluster with containerd as the container runtime, including network plugin installation.
Kubernetes 1.20 marks the deprecation of Docker support, explaining that Docker’s heavyweight nature and the maintenance burden of the dockershim layer drove the change, while reassuring developers that OCI‑compatible images still run unchanged, though operators must switch to containerd or CRI‑O.
