K3s is a lightweight Kubernetes distribution designed for resource-constrained environments and edge computing. It simplifies the deployment and management of Kubernetes clusters by reducing the overhead associated with traditional Kubernetes installations. K3s is particularly popular for IoT devices, ARM processors, and environments where quick setup and minimal resource usage are critical.
When a node in a K3s cluster runs out of disk space, it can lead to various operational issues. The most common symptom is the inability to schedule new pods on the affected node. Existing pods may also experience degraded performance or fail to operate correctly. The error message 'NodeOutOfDisk' is typically observed in the node's status or in the logs, indicating that the node has insufficient disk space to continue normal operations.
The 'NodeOutOfDisk' issue arises when a node's available disk space falls below a critical threshold. Kubernetes nodes require sufficient disk space to store container images, logs, and other operational data. When disk space is exhausted, Kubernetes cannot allocate resources for new pods, and existing pods may be evicted or fail to start. This issue is particularly common in environments with limited storage capacity or where disk usage is not actively monitored.
To resolve the 'NodeOutOfDisk' issue, follow these steps to free up disk space or add additional storage:
Use the following command to check disk usage on the affected node:
df -h
This command provides an overview of disk space usage, helping you identify which directories or files are consuming the most space.
Remove unused Docker images to free up space:
docker image prune -a
This command deletes all unused images, freeing up disk space.
Check and clear logs that are no longer needed:
journalctl --vacuum-time=1d
This command removes logs older than one day, which can significantly reduce disk usage.
If disk space is still insufficient, consider adding additional storage to the node. This can be done by attaching a new disk or expanding existing storage volumes.
By following these steps, you can effectively resolve the 'NodeOutOfDisk' issue and ensure your K3s cluster operates smoothly. Regular monitoring and maintenance of disk usage are recommended to prevent future occurrences.
(Perfect for DevOps & SREs)
(Perfect for DevOps & SREs)
