AWS Classroom Series – 10/Jul/2020

Networking contd..

• Answer to previous class question

10.11.0000000   0.00000000

10.11.0.0/23 G

10.11.0000001   0.00000000
255.255.254.0
10.11.2.0/23 F
10.11.4.0/23 S
10.11.6.0/23 3
10.11.8.0/23 4
10.11.0000101   0.00000000
10.11.10.0/23 5
10.11.00100000.00000000
10.11.32.0/19
255.255.224.0

• When we create a subnet we have two ipaddress which are reserved (networkid and broadcast address), when we create a subnet in AWS
  • x.x.x.0 => Network address
  • x.x.x.1 => Reseved by AWS for the vpc router
  • x.x.x.2 => Reserved by AWS for the DNS server
  • x.x.x.3 => Reserved by AWS for future usage
  • x.x.x.255 => Broadcast address
• First four ip address and last ip address (total 5) are reserved. IN AWS the formula for the host size is 2^n-5

Lets create a VPC in AWS

• In AWS VPC is created at the Region level and subnets are scoped at AZ level
• Regions in AWS will have a code in the pattern of <cont>-<direction>-<number> eg us-west-2, ap-south-1 and AZ will have code of <region><a-z> eg us-west-2a,us-west-2b,us-west-2c
• Navigate to aws console Refer Here
• Every AWS Region will have a Default VPC
• Now lets create our vpc
• Generally when we create a network, we might need router, In AWS router is called as route table. Whenever we create a vpc a default rotue table (router) is created. It will have following rules
  • All the traffic with in vpc is allowed i.e. all devices in subnets can communicate with each other
• Network (VPC) which we created logically looks as shown below
• To enable internet connectivity (dual) to your vpc, we need to create internet gateway
• Current state logically looks as shown below
• To get internet to our subnets, we need to establish route table routes to internet gateway

Next steps

• Create route table rules for internet connectivity?
• What are public and private subnets?
• How do my private subnets connect to internet?
• How can i communicate across different vpc’s