critest is a comprehensive test suite designed to validate that a given container runtime implementation is fully compliant with the Kubernetes CRI specification. It can be used to benchmark and verify the functionality and performance of any CRI-compatible runtime.
sudo systemctl start containerd sudo systemctl enable containerd # Ensures containerd starts on boot sudo systemctl status containerd # Verify it's running
Whether you are debugging a ? Share public link cri file system tools install
In the early days of Kubernetes, Docker was the primary container runtime. However, as the ecosystem matured, the need for more lightweight, modular, and Kubernetes-native runtimes became apparent. This led to the deprecation of Docker as a runtime in favor of CRI-compliant runtimes like containerd and CRI-O , which are now the standard in Kubernetes clusters.
To get the absolute latest features—especially for filesystem checkpointing—build from source. critest is a comprehensive test suite designed to
: An specialized tool that allows users to generate CPK files directly from within a Microsoft Excel worksheet list. System Requirements Operating System : Designed for Windows 7, 8.1, 10, and 11. : Requires .NET Framework 4.0 or higher to run. Architecture
Usually involves downloading the .exe (for Windows) or compiling the source using Visual Studio. Share public link In the early days of
For the purpose of this article, we will focus on the most common installation targets: (for container filesystem inspection) and CRIU-related filesystem tools (for process checkpointing that interacts closely with file descriptors and /proc filesystem).
: You can install the cri-tools package directly using apt .
| Aspect | crictl | ctr | nerdctl | |--------|----------|-------|-----------| | | Kubernetes node debugging | Containerd development/debugging | Daily container management | | Interface | CRI API (Kubernetes perspective) | Containerd native API | Docker-compatible CLI | | Kubernetes Awareness | ✓ Shows Pods and sandbox containers | ✗ Shows only containers (K8s containers require -n k8s.io ) | ⚠️ Limited (requires -n k8s.io for K8s containers) | | Docker Compatibility | ✗ | ✗ | ✓ (90%+ command compatibility) | | Container Creation | Limited (primarily debugging) | ✓ (low-level) | ✓ (full lifecycle) | | Build Capabilities | ✗ | ✗ (needs external tools) | ✓ ( nerdctl build ) | | Compose Support | ✗ | ✗ | ✓ ( nerdctl compose ) | | Logs Access | ✓ | ✗ | ✓ | | Interactive Shell | ✓ ( exec ) | ✗ | ✓ | | Rootless Mode | ✗ | ✗ | ✓ | | Learning Curve | Moderate | Steep | Gentle |
To purge dangling images, stopped containers, and leaked filesystem layers causing disk pressure: sudo crictl rmi --prune Use code with caution. Troubleshooting Common Installation Errors Error: "Connect: No Such File or Directory"