# devops-exercises | Arie Bregman | Knowledge Base | Instagit

Linux, Jenkins, AWS, SRE, Prometheus, Docker, Python, Ansible, Git, Kubernetes, Terraform, OpenStack, SQL, NoSQL, Azure, GCP, DNS, Elastic, Network, Virtualization. DevOps Interview Questions

GitHub Stars: 81.3k

Repository: https://github.com/bregman-arie/devops-exercises

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## Articles

### [Migrating Monolithic Applications to a Microservices Architecture: Containerization and Orchestration Guide](/bregman-arie/devops-exercises/migrating-monoliths-microservices-containerization-orchestration)

Learn to migrate monoliths to microservices using containerization and orchestration. Decompose domains, containerize services, and secure with Kubernetes, CI/CD, observability, and service mesh.

- Tags: migration-guide
- Published: 2026-02-28

### [How Prometheus Uses Service Discovery to Dynamically Monitor Ephemeral Kubernetes Services](/bregman-arie/devops-exercises/prometheus-service-discovery-ephemeral-kubernetes-monitoring)

Learn how Prometheus uses Kubernetes service discovery to automate monitoring of dynamic, ephemeral services. Track metrics without manual updates as containers scale or restart.

- Tags: internals
- Published: 2026-02-28

### [Core Principles of Chaos Engineering: A Practical Guide to Testing System Resilience](/bregman-arie/devops-exercises/chaos-engineering-principles-production-resilience-testing)

Explore the core principles of Chaos Engineering and learn how to test system resilience. This practical guide covers defining steady state hypothesizing continuity introducing failures observing deviations and automating exper...

- Tags: tutorial
- Published: 2026-02-28

### [How to Use Ansible for Automating EC2 Instances and RDS Databases: A Complete Guide](/bregman-arie/devops-exercises/ansible-automating-cloud-infrastructure-ec2-rds)

Automate AWS EC2 instances and RDS databases with Ansible. Use agentless architecture and cloud modules to provision and manage your infrastructure via YAML playbooks. Learn how now.

- Tags: how-to-guide
- Published: 2026-02-28

### [Terraform State Backends: How S3, Azure Blob, and GCS Impact Team Collaboration, Security, and Performance](/bregman-arie/devops-exercises/terraform-state-backends-team-collaboration-security)

Explore Terraform state backends like S3 Azure Blob and GCS Understand their impact on team collaboration security and performance for efficient infrastructure management

- Tags: architecture
- Published: 2026-02-28

### [Disaster Recovery Strategies for Stateful Applications on Kubernetes: Architectural Patterns and Best Practices](/bregman-arie/devops-exercises/disaster-recovery-strategies-stateful-applications-kubernetes)

Learn Kubernetes disaster recovery strategies for stateful applications. Explore architectural patterns, persistent storage, backup tools, and replication for RTO/RPO success.

- Tags: architecture
- Published: 2026-02-28

### [Kubernetes Services (ClusterIP, NodePort, LoadBalancer) vs Ingress Controllers: Exposing Applications Externally](/bregman-arie/devops-exercises/kubernetes-services-vs-ingress-controllers-external-exposure)

Understand Kubernetes Services (ClusterIP NodePort LoadBalancer) vs Ingress controllers for external application access. Learn their differences to choose the right external exposure method.

- Tags: deep-dive
- Published: 2026-02-28

### [TLS/SSL Handshake Process: Critical Steps, Pitfalls, and Diagnosis Methods](/bregman-arie/devops-exercises/tls-ssl-handshake-process-negotiation-failures)

Master the TLS/SSL handshake! Explore critical steps, common pitfalls like version mismatches, and diagnostic tools such as openssl s_client to ensure secure connections.

- Tags: deep-dive
- Published: 2026-02-28

### [AWS VPC Default Configuration Security Risks: 5 Critical Vulnerabilities and Mitigation Strategies](/bregman-arie/devops-exercises/aws-vpc-default-configurations-security-risks)

Discover 5 critical security risks in default AWS VPC configurations, including internet exposure and public IPs. Learn effective mitigation strategies for robust cloud security.

- Tags: security
- Published: 2026-02-28

### [How to Implement Sophisticated Network Policies in Kubernetes for Least-Privilege Communication](/bregman-arie/devops-exercises/kubernetes-network-policies-least-privilege-communication)

Master Kubernetes network policies for least-privilege communication. Learn to implement default deny and whitelist traffic using labels, CIDRs, and OPA Gatekeeper.

- Tags: how-to-guide
- Published: 2026-02-28

### [Prometheus Metric Collection Strategies: Comparing Pushgateway, Node Exporter, and cAdvisor](/bregman-arie/devops-exercises/prometheus-pushgateway-node-exporter-cadvisor-collection-strategies)

Compare Prometheus metric collection strategies. Learn how Pushgateway, Node Exporter, and cAdvisor gather metrics for different applications, enabling effective monitoring.

- Tags: deep-dive
- Published: 2026-02-28

### [How the Linux Kernel's CFS Scheduler and OOM Killer Impact Containerized Applications](/bregman-arie/devops-exercises/linux-kernel-scheduler-oom-killer-container-impact)

Understand how the Linux CFS scheduler and OOM Killer affect containerized apps. Learn about cgroup tunables like cpu.shares and memory.limit_in_bytes for performance tuning and isolation.

- Tags: internals
- Published: 2026-02-28

### [Highly Available and Resilient Multi-AWS VPC Architectures: Design Patterns for Private Subnets and Inter-VPC Communication](/bregman-arie/devops-exercises/ha-multi-aws-vpc-architecture-private-subnets)

Learn key design patterns for highly available, resilient multi-AWS VPC architectures. Discover best practices for private subnets and inter-VPC communication using Transit Gateway and NAT Gateways.

- Tags: architecture
- Published: 2026-02-28

### [How GitOps Workflow Integrates with Kubernetes Operators and Controllers for Automated Infrastructure Management](/bregman-arie/devops-exercises/gitops-workflow-kubernetes-operators-automation)

Discover how GitOps workflow integrates with Kubernetes operators and controllers for automated infrastructure and application lifecycle management using version control, Argo CD, and Custom Resources.

- Tags: architecture
- Published: 2026-02-28

### [Performance and Cost Implications of Choosing Between AWS S3, EBS, and EFS for Cloud-Native Data](/bregman-arie/devops-exercises/aws-s3-ebs-efs-performance-cost-implications)

Compare AWS S3, EBS, and EFS performance and costs for cloud-native data. Understand access patterns, latency, and sharing needs to select the best storage solution for your application.

- Tags: performance
- Published: 2026-02-28

### [How to Debug Kubernetes Pod Crash Loops with Advanced kubectl Commands and Log Analysis](/bregman-arie/devops-exercises/debug-kubernetes-pod-crash-loops-advanced-kubectl)

Effectively debug Kubernetes pod crash loops. Learn advanced kubectl commands like describe and logs --previous, plus log analysis techniques, to quickly resolve issues.

- Tags: how-to-guide
- Published: 2026-02-28

### [Architectural Trade-offs Between Argo CD and Jenkins for GitOps Continuous Deployment Pipelines](/bregman-arie/devops-exercises/argo-cd-vs-jenkins-gitops-architecture)

Compare Argo CD and Jenkins for GitOps CI CD pipelines. Understand architectural trade-offs: Argo CD's native reconciliation vs Jenkins' external orchestration for Kubernetes deployments.

- Tags: architecture
- Published: 2026-02-28

### [How SNAT and DNAT Function at the Packet Level in NAT Devices: Endpoint Identification and Security Implications](/bregman-arie/devops-exercises/snat-dnat-packet-level-implications)

Understand SNAT and DNAT packet level functions in NAT devices. Discover how they impact endpoint identification and security to enhance your network knowledge.

- Tags: deep-dive
- Published: 2026-02-28

### [Advanced Security Considerations for Hardening Container Runtimes and Kubernetes Network Policies in Production](/bregman-arie/devops-exercises/advanced-container-security-kubernetes-network-policies)

Secure your production Kubernetes by hardening container runtimes and network policies. Learn to implement advanced security like OCI compliance, user namespaces, seccomp, and default-deny network policies.

- Tags: deep-dive
- Published: 2026-02-28

### [OSI Layer 3 vs Layer 4: Packet Handling and Routing Responsibilities](/bregman-arie/devops-exercises/osi-layer-3-vs-layer-4-packet-handling)

Understand OSI Layer 3 vs Layer 4 packet handling. Layer 3 routes across networks via IP, while Layer 4 ensures reliable app delivery using ports. Learn the core differences.

- Tags: deep-dive
- Published: 2026-02-28

### [When to Use Kubernetes Deployments, StatefulSets, or DaemonSets in Production](/bregman-arie/devops-exercises/kubernetes-deployments-statefulsets-daemonsets-production-workloads)

Learn when to use Kubernetes Deployments for stateless apps, StatefulSets for stateful apps needing stable identities, and DaemonSets for node-level agents. Master production workload choices.

- Tags: deep-dive
- Published: 2026-02-28

### [How TCP/IP Dynamic Window Scaling and Selective Acknowledgment Optimize Throughput in High‑Latency Networks](/bregman-arie/devops-exercises/tcpip-window-scaling-selective-acknowledgment-throughput)

Learn how TCP/IP dynamic window scaling and SACK optimize throughput in high-latency networks by removing the 65KB limit and enabling precise retransmissions.

- Tags: performance
- Published: 2026-02-28

### [AWS IAM Roles vs Users and Groups: Nuances for Granular Access Control in Complex Cloud Environments](/bregman-arie/devops-exercises/aws-iam-roles-users-groups-granularity)

Master AWS IAM: Learn roles vs users and groups to achieve granular access control in complex cloud environments. Understand trust policies and session permissions.

- Tags: deep-dive
- Published: 2026-02-28

### [How Kubernetes Control Plane Components Orchestrate Cluster State and Desired Configurations](/bregman-arie/devops-exercises/kubernetes-control-plane-component-orchestration)

Discover how Kubernetes control plane components like kube-apiserver, etcd, kube-scheduler, and kube-controller-manager orchestrate cluster state and configurations. Learn about declarative and eventually-consistent systems.

- Tags: internals
- Published: 2026-02-28