Steps to create site to site VPN in AWS

1. First create Virtual Private Gateway and attach it to the VPC
2. Create customer Gateway with the inputs shared to us by the customer
3. Create a Site to Site VPN with the details shared to us by the customer
4. Choose the Customer Gateway and Virtual Private Gateway which you created earlier while creating a site to site VPN.
5. Choose the Subnet which is attached to the VPC ie the EC2 which is associated with Private Subnet, Navigate to its route table and add routes by choosing the on-prem CIDR, point it towards Virtual Private Gateway
6. Go to site to site VPN and download the configuration file while doing this it will ask fill up the details as shared by the customer such as on-premise Firewall name, version and send the downloaded file to the on-premise firewall admin.

The Details you ask the customer before creating a Site to Site VPN are as follows.

1.Onpremise CIDR -
2.Firewall Public IP :
3.Name of the Firewall -
4.Private IP range of Onpremise site location :
5.Contact details of On-premise Network/Firewall Admin.

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