Rancher is an open-source platform designed to manage Kubernetes clusters. It provides a comprehensive suite of tools to deploy, manage, and scale containerized applications across multiple clusters. Rancher simplifies Kubernetes cluster management by offering a user-friendly interface and robust features for monitoring, security, and application deployment.
When managing Kubernetes clusters with Rancher, you may encounter the issue of Node Disk Pressure. This symptom is typically observed when a node in your cluster experiences insufficient disk space, leading to potential disruptions in application performance and stability.
Common signs of Node Disk Pressure include:
The root cause of Node Disk Pressure is often insufficient disk space on the node. Kubernetes monitors node resources and applies pressure when disk space is low, which can lead to pod eviction to free up resources. This is crucial for maintaining cluster health but can disrupt workloads.
Disk pressure occurs when the available disk space falls below a certain threshold. Kubernetes uses this metric to decide when to evict pods to prevent the node from running out of space completely. For more details on how Kubernetes handles disk pressure, refer to the Kubernetes documentation on node pressure eviction.
To address Node Disk Pressure, you need to either free up disk space or add additional storage to the affected node. Here are the steps you can take:
du and find:du -sh /* | sort -h
rm -rf /path/to/unnecessary/files
docker system prune -a
kubectl describe node <node-name>
By understanding and addressing Node Disk Pressure, you can ensure the smooth operation of your Kubernetes clusters managed by Rancher. Regular monitoring and maintenance of node resources are essential to prevent such issues from affecting your applications. For more information on managing Kubernetes resources, visit the Rancher documentation.
(Perfect for DevOps & SREs)
(Perfect for DevOps & SREs)
