How to Feed Real Cluster Data Into Kubernetes VPA for Accurate Sizing

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A technical guide explains how to gather the actual inputs needed to use the Vertical Pod Autoscaler (VPA) recommender effectively in a live Kubernetes or OpenShift cluster. Key commands using kubectl or oc retrieve node-level allocatable resources, namespace ResourceQuotas, and LimitRange ceilings, all of which can silently block or skew VPA resize operations. LimitRange in particular is highlighted as a commonly overlooked constraint that can cause in-place resize patches to fail without clear error messages. The guide also covers how to pull current deployment resource requests and limits as a baseline before VPA makes any changes. Both kubectl and oc are supported interchangeably, with a few OpenShift-specific alternatives noted for quota management at the project level.

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AWS Developer Associate Certification: Why Hands-On Practice Beats Theory

Ntombizakhona Mabaso, an AWS Certified Developer Associate, has shared her certification journey and key preparation strategies on DEV Community. She advises candidates to prioritize building real projects over passive study, arguing that practical experience makes troubleshooting and exam questions far easier to handle. Mabaso also highlights that AWS allows higher-level certifications, such as the DevOps Engineer Professional, to automatically renew qualifying lower-level credentials, offering a more efficient path to staying current. For those not yet ready to pursue a Professional-level exam, AWS Skill Builder now lets eligible certification holders renew through maintenance activities without retaking the full paid exam. Her recommended hands-on exercises include building REST APIs with Lambda and DynamoDB, setting up CI/CD pipelines, and debugging IAM permission issues within real AWS environments.

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ProgrammingDEV Community ·

How to Properly Evaluate a Testing Tool Beyond Feature Checklists

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ProgrammingDEV Community ·

Public const constructors can silently bypass Dart factory validation logic

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ProgrammingDEV Community ·

Horizontal vs Vertical Scaling: Why Stateless Apps Handle Traffic Spikes Better

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