Every AWS service is publicly exposed (public URL) VPC Endpoints (powered by AWS PrivateLink) allow you to connect AWS services using a private network instead of using the public internet They are redundant and scale horizontally They remove the nee...
We can use a Bastion Host to SSH into our private EC2 instances The bastion is in the public subnet which is then connected to all other private subnets Bastion Host security group must be tightened
Allows resources (e.g: EC2 instances) in a VPC to connect to the internet It scales horizontally and is highly available and redundant Must be created separately from a VPC One VPC can only connect to one IGW and vice versa Internet Gateways on their...
AWS reserves 5 IP addresses (first 4 and last 1) in each subnet These 5 IP addresses are not available for use and can't be assigned to an EC2 instance e.g: If CIDR block 10.0.0.0/24, reserved IP address are 10.0.0.0 - Network Address 10.0.0.1 - rese...
VPC = Virtual Private Cloud We can have multiple VPCs in an AWS region (max 5 per region - soft limit) Max CIDR per VPC is 5 for each CIDR Min size is /28 (16 IP addresses) Max size is /16 (65,536 IP addresses) Because VPC is private, only the priv...
All new AWS accounts have a default VPC New EC2 instances are launched into the default VPC if no subnet is specified Default VPC has internet connectivity and all EC2 instances inside it have a public IPv4 address We also get public and private D...