VPC networking components
A VPC network consists of certain components. We will now look briefly at these components.
ENI
ENI is a virtual network interface. It is a communication hub for an EC2 instance that enables network communication on an instance. An EC2 instance can have one or more network interfaces. When any EC2 instance is created inside a VPC, by default, a network interface is also created and attached to it. The default network interface created while launching an instance is called a primary network interface of the instance. This primary network interface also gets one primary IPv4 address from the subnet's available IP range. You cannot detach a primary network interface from an EC2 instance and attach to another. However, although you cannot detach a primary network interface, AWS allows us to create additional network interfaces that can be attached to the EC2 instance. Additional network interfaces are also called secondary network interfaces. Secondary network interfaces...
