INTERVIEW-LEARNING-LINKS

 Azure Site-to-Site VPN — Detailed Resource-by-Resource Creation This explains exactly how every Azure resource is created , what it does, where it resides, and how all components connect in Microsoft Azure . On-Prem Network (192.168.1.0/24)         |    [Firewall/VPN Device]         |    Public IP: 1.2.3.4         | ================ INTERNET =================         |    Azure VPN Gateway (Public IP)         |    GatewaySubnet         |    Azure VNet (10.0.0.0/16)         |  ┌──────────────┬──────────────┐  |              |              | AppSubnet    DBSubnet      WebSubnet 10.0.1.0/24 10.0.2.0/24 10.0.3.0/24 🏗️ STEP 1 — CREATE RESOURCE GROUP Field Value Resource Group    RG-Ne...

   1. Virtual Network (VNet) 📌 One-paragraph explanation A Virtual Network (VNet) is the core private networking space in Azure where all cloud resources communicate securely. It is used to isolate workloads, control IP ranges, and create a private environment similar to a traditional data center network but fully software-defined in the cloud. 🔍 Details Where used: Hosting VMs, AKS clusters, databases, internal services Connected services: VM, Load Balancer, Application Gateway, Azure Firewall, Private Endpoint Dependencies: None (foundation component) Purpose in architecture: Acts as the main “network boundary” for all resources 🧩 2. Subnet 📌 One-paragraph explanation A subnet is used to divide a VNet into smaller logical networks so that different layers of an application (web, app, database) can be separated and controlled independently for security and traffic management. 🔍 Details Where used: Tiered architectures (web/app/db layers), microse...

  AWS Compute Services Explained 1. EC2 (Elastic Compute Cloud) What It Is Amazon EC2 provides virtual servers in the cloud. Used For Hosting applications Running websites Databases Enterprise workloads Virtual machines on demand Benefits Scalable Flexible instance types Pay-as-you-go pricing Example Hosting a Java web application on Linux servers. 2. Auto Scaling Groups (ASG) What it is used for ASG automatically adds or removes EC2 servers based on demand . You use it for: Handling traffic spikes (e.g., sales, exams, events) Keeping applications always available Replacing failed servers automatically 👉 Think of it as: “Auto-adjusting server capacity” 3. EC2 Spot Instances What it is used for Spot Instances use unused AWS capacity at very low cost . You use it for: Batch processing jobs Big data workloads CI/CD pipelines ML training (non-critical jobs) ⚠️ AWS can stop them anytime. 👉 Think of it as: “Cheap but interruptible cloud servers” 4. Dedicated Hosts What it is used for D...

  Kubernetes Core Resources Explained 1. Pods What It Is A Pod is the smallest deployable unit in Kubernetes. It contains one or more containers that share: Network Storage Lifecycle Used For Running application containers Grouping tightly coupled containers together Example A web application container running inside a pod. 2. Deployments What It Is A Deployment manages Pods and ReplicaSets. Used For Rolling updates Application version upgrades Scaling applications Self-healing applications Example Deploying 3 replicas of an NGINX application. 3. ReplicaSets What It Is A ReplicaSet ensures a specified number of pod replicas are always running. Used For High availability Maintaining desired pod count Example Keeping 5 backend pods running at all times. 4. DaemonSets What It Is A DaemonSet ensures one pod runs on every node (or selected nodes). Used For Monitoring agents Log collectors Security agents Example Running Fluentd or Prometheus Node Exporter on all nodes. 5. StatefulSets W...

 Azure Site Recovery an earlier tool for migration: Thought purpose built for Disaster Recovery ASR: Azure Site Recovery Yes — Azure Site Recovery (ASR) is commonly used as a migration tool , even though its primary purpose is disaster recovery. How ASR Is Used for Migration Organizations use ASR to perform: Lift-and-shift migrations VMware to Azure migrations Hyper-V to Azure migrations Physical server to Azure migrations ASR replicates workloads continuously from on-premises infrastructure to Azure. During the final cutover, the replicated VM is started in Azure with minimal downtime. Migration Workflow Using ASR Typical Flow Discover on-prem servers Enable replication Continuous data synchronization Test failover (optional) Planned failover/cutover Azure VM becomes production workload This approach minimizes: Downtime Data loss Manual rebuild effort Why ASR Is Popular for Migration ASR vs Azure Migrate Real-World Use Case Example: Company has 200 VMware VMs on-premises. The...