CodeWithClarity

1. What is Infrastructure as Code (IaC)? First, imagine you want to create infrastructure in Google Cloud. For example, you need: 2 Virtual Machines (VMs). 1 VPC network. 1 Firewall rule. 1 Load Balancer. There are three ways to create these resources. 1. Google Cloud Console (GUI) You manually click buttons and fill in details to create resources. 2. Cloud Shell (CLI) You execute commands to create resources. 3. Terraform (Infrastructure as Code) You write configuration files that describe the infrastructure you need. Terraform creates it automatically. Simple definition: Infrastructure as Code (IaC) means creating and managing cloud infrastructure using code instead of manually creating resources. For example, instead of manually creating 10 VMs, you write a Terraform configuration and Terraform creates them for you. 2. Why do we need Infrastructure as Code? Suppose your company has three environments: Development environment Testing environment Production environment You need almos...

  Cloud CDN Overview Cloud CDN (Content Delivery Network) uses Google's globally distributed edge locations (Points of Presence) to cache content closer to users, improving performance and reducing load on backend servers. Key Benefits Faster content delivery through edge caching. Reduced latency for end users. Lower backend serving costs. Easy to enable on an Application Load Balancer backend service. How Cloud CDN Works Components Application Load Balancer Backend services: Managed Instance Groups (VMs) Cloud Storage Buckets Cloud CDN Edge Cache Locations Request Flow 1. First Request (Cache Miss) User requests content. Request reaches nearest CDN edge location. CDN checks its cache. Content is not found → Cache Miss . CDN may check nearby cache locations. If still unavailable: Request is sent to the Application Load Balancer. Load Balancer forwards it to the appropriate backend. Backend returns the content. If cacheable, CDN stores a copy at the edge location. 2. Subsequent Re...

  Google Cloud Application Load Balancer (Layer 7) Let's understand this in a simple, beginner-friendly way. 1. What is an Application Load Balancer? An Application Load Balancer (ALB) works at Layer 7 – Application Layer of the OSI model. It distributes HTTP/HTTPS traffic based on application-level information, such as: URL path ( /users , /payments ) Hostname ( api.example.com ) HTTP headers Example: A user visits www.example.com . /products → Product service /payments → Payment service /images → Cloud Storage The load balancer checks the URL and sends the request to the correct backend. 2. What can be used as a backend? Google Cloud Application Load Balancer can route traffic to: Compute Engine VMs Google Kubernetes Engine (GKE) Cloud Run Cloud Storage (backend buckets, supported by global external ALB) External backends over the internet or hybrid connectivity 3. Types of Application Load Balancers Type Meaning Global external Accepts internet traffic and supports global, mu...

  Think of a Managed Instance Group (MIG) as a Kubernetes ReplicaSet, but for VMs . As a backend developer, imagine you need 10 identical application servers running your Spring Boot application. Instead of manually creating and managing 10 VMs, you: Define a blueprint ( Instance Template ) Tell Google Cloud to maintain 10 copies Google automatically creates, heals, scales, and updates them Core Components 1. Instance Template = Blueprint Contains VM configuration: Machine type OS image Startup scripts Metadata Network settings Example: Template: - Ubuntu - 4 vCPU - 16 GB RAM - Install Java - Deploy Spring Boot app This template acts like a Docker image for VMs. 2. Managed Instance Group Suppose: Desired instances = 3 Google creates: VM-1 VM-2 VM-3 All from the same template. MIG  ├── VM-1  ├── VM-2  └── VM-3 Self-Healing Feature If one VM crashes: VM-2 dies MIG notices: Current = 2 Desired = 3 Automatically creates: VM-2 (new) using the same template. This is call...

  Shared VPC and VPC Network Peering Peering means creating a direct private connection between two networks so they can communicate with each other. Simple Real-World Analogy Imagine two separate office buildings: Building A has its own internal network. Building B has its own internal network. Normally, employees would communicate through the public internet. With peering , you build a private bridge between the two buildings. Building A  <==== Private Bridge ====>  Building B Now traffic: Doesn't go over the public internet Is faster Is more secure Uses private addresses In GCP VPC Peering Two VPC networks are connected directly: VPC-A  <==== Peering ====>  VPC-B After peering: VM in VPC-A can talk to VM in VPC-B Uses private RFC1918 IPs (10.x.x.x, 172.16.x.x, 192.168.x.x) No VPN required No public IP required VPC-A VM = 10.1.1.10 VPC-B VM = 10.2.1.20 After peering: 10.1.1.10 --- > 10.2.1.20 communication works privately. VPC Peering is a n...

  Cloud Peering Used to connect your network to Google public services such as: Google Cloud Gmail YouTube Google APIs Google Workspace Two options: Direct Peering Carrier Peering 1. Direct Peering Definition: A direct connection between your network and Google's network. How it works: Uses BGP route exchange. Connects at a Google Edge PoP (Point of Presence) . Google Edge PoP (Point of Presence) is a physical location where Google's global network connects to other networks and the Internet . Think of it like this: 🏢 Your Company Network → 🌐 Google Edge PoP → ⚡ Google Global Backbone → ☁️ Google Services Simple Analogy Imagine Google owns a huge highway network. Google Edge PoP = Highway Entry Gate Once your traffic enters through that gate, it travels on Google's fast private backbone network. Features: Access to all Google services. 10 Gbps per link. Lower latency than normal internet routing. No SLA. Requirements: Must be present at a Google Edge PoP. Must meet...

  GCP Interconnect Services Problem Statement A company has an on-premises datacenter and wants to communicate with resources running inside Google Cloud VPC. Possible options: Cloud VPN Dedicated Interconnect Partner Interconnect Cross-Cloud Interconnect The choice depends on bandwidth, cost, location, and business requirements. Dedicated Interconnect What is it? Dedicated Interconnect provides a private physical connection between an on-premises network and Google's network. Company Datacenter          |     Company Router          |      Fiber Link          |     Google Router          |       Cloud Router          |          VPC The company and Google meet at a common colocation faci...