3.35 What is an AWS ENI

An AWS ENI, or Elastic Network Interface, is a virtual network interface that can be attached to an Amazon Web Services (AWS) instance. It acts as a gateway between the instance and the network, allowing the instance to communicate with other resources on the network, such as other instances, load balancers, and databases.

An ENI can be configured with one or more IP addresses, and can also be associated with multiple security groups, which control inbound and outbound traffic to and from the instance. This allows for greater flexibility and security in network configurations.

ENIs can also be moved between instances, allowing for easy migration and redundancy. They can also be used to create custom network topologies, such as multi-tiered applications with separate subnets for web, application, and database servers.

AWS offers several types of ENIs, including standard, enhanced, and elastic. Each type has different capabilities and performance characteristics, allowing users to choose the best option for their specific needs.

Overall, an AWS ENI is an essential component of any AWS network architecture, providing a flexible and secure way to connect instances to the network and other resources.