Cloud

Introduction TL;DR: Kubernetes Volumes provide a durable storage solution to solve the ephemeral nature of container filesystems, ensuring data persists even when a Pod restarts. The core of Kubernetes storage is an abstraction layer consisting of three key objects: PersistentVolume (PV), PersistentVolumeClaim (PVC), and StorageClass. An administrator defines available storage as a PV, a user requests storage with a PVC, and a StorageClass enables the dynamic, automatic provisioning of PVs to satisfy PVCs, streamlining storage management in cloud environments. By default, a container’s filesystem is ephemeral. Any data created inside a container is lost when the container is terminated and restarted. To run stateful applications like databases, it’s essential to have a mechanism for persistent storage. Kubernetes Volumes address this by decoupling the storage lifecycle from the Pod lifecycle. A Volume is essentially a directory, accessible to the containers in a Pod, whose data can be preserved across container restarts. ...

Introduction TL;DR: The Kubernetes NodePort service exposes an application to external traffic by opening a specific port on every node in the cluster. It maps an external port (default range: 30000-32767) to an internal service’s port, allowing access via <NodeIP>:<NodePort>. NodePort is a straightforward way to expose services, primarily used for development, testing, or demo purposes, as it lacks the production-grade features of LoadBalancer or Ingress. The Kubernetes NodePort is a fundamental service type that provides external access to applications running within a cluster. In Kubernetes, Pods are ephemeral and have dynamic IP addresses, making direct access unreliable. Services solve this by providing a stable endpoint. A NodePort service builds upon the internal-only ClusterIP service by making that service accessible from outside the cluster through a static port on each worker node’s IP address. ...

What Is HAProxy: A Deep Dive into the High Availability Load Balancer HAProxy (High Availability Proxy) is a cornerstone of modern web architecture, functioning as a premier open-source load balancer and reverse proxy for TCP and HTTP-based applications. Since its creation in 2000, it has become the go-to solution for managing traffic and ensuring service uptime for countless high-traffic websites. By intelligently distributing incoming requests across a farm of backend servers, HAProxy prevents any single server from becoming a bottleneck, thereby maximizing performance and guaranteeing high availability. ...

Kubernetes Pod Resource Management: Requests, Limits, and QoS Question: “How do I control CPU and memory usage for Pods in Kubernetes?” If resource limits are not set, a single Pod can consume excessive CPU or memory, causing instability across the cluster. Kubernetes provides Requests and Limits to manage resources effectively.

In this guide, we’ll explore Longhorn, a lightweight, reliable, and open-source distributed block storage system for Kubernetes. You’ll learn what Longhorn is, how it works, how to install it using Helm, and how to monitor it with Grafana and Prometheus. Table of Contents 1. What is Longhorn? Longhorn turns the local disks of your Kubernetes cluster nodes into persistent volumes — making stateful apps like databases possible in Kubernetes. Think of it this way: ...