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VPC & SUBNETTING

VPC & Subnetting: The Foundation of Cloud Networking

DOWNLOADING CONCEPT: 1. THE VIRTUAL PRIVATE CLOUD (VPC)...
  • ↳When you create an AWS account, you don't just throw servers onto the public internet.
  • ↳You create a VPC (Virtual Private Cloud).
  • ↳A VPC is a logically isolated section of the AWS Cloud where you launch resources in a virtual network that you completely define.
  • ↳You assign a CIDR block to the VPC (e.g., 10.0.0.0/16), which gives you 65,536 private IP addresses.
  • ↳This is your sandbox.
  • ↳No one outside the VPC can talk to the resources inside it unless you explicitly allow them to.
▲ LIVE INCIDENTYou deployed a brand new EC2 instance into a Public Subnet and assigned it a Public IP address. However, when you try to ping 8.8.8.8 from the instance, it times out.
sre@arena:~/cloud-vpc-1
sre@arena:~$ aws ec2 describe-route-tables --filters "Name=association.subnet-id,Values=subnet-12345678"