Most Asked DevOps Interview Questions

321. How does Kubernetes handle 'rolling updates' and rollbacks of application deployments?

Kubernetes handles rolling updates by creating a new version of the application while gradually shifting traffic to it, ensuring minimal downtime. If issues occur, Kubernetes can roll back to the previous version by reverting to the old configuration.

322. What are Labels and Selectors in Kubernetes, and why are they significant?

Labels in Kubernetes are key-value pairs attached to objects like pods or services for identification and categorization. Selectors are used to filter and target objects based on their labels. They are significant because they enable flexible management, grouping of resources, and support various Kubernetes features like service discovery and deployment strategies.

323. Describe the role of a Service Mesh like Istio in a Kubernetes environment.

A Service Mesh like Istio in a Kubernetes environment provides advanced networking, security, and observability features for managing communication between services. It enhances control over traffic routing, enforces security policies, and offers monitoring tools for better management of microservices.

324. How can you monitor and troubleshoot applications running in a Kubernetes cluster?

• Using monitoring tools like Prometheus and Grafana to track metrics.
• Utilizing centralized logging with tools like Elasticsearch and Kibana.
• Implementing distributed tracing with tools like Jaeger.
• Configuring health checks for applications.
• Using debugging tools like kubectl exec and kubectl logs.
• Setting up alerting rules for critical issues.
• Monitoring resource usage and performance.

325. What is the different between node selector and node affinity?