Before you use Elastic Network Interface (ENI), you need to understand the following concepts.
Primary or secondary network interfaces
- A network interface created when the CVM of VPC is created is a primary network interface. A network interface created by the user is a secondary network interface.
- The primary network interface cannot be bound or unbound, while the secondary network interface can.
Primary Private IP
- The primary private IP of the ENI can be randomly allocated by the system or set by the user when the ENI is created.
- The primary private IP of the primary network interface can be modified, but the primary private IP of the secondary network interface cannot.
Secondary Private IP
- The secondary private IP bound to the primary IP of the ENI is configured by the user when he creates or edits the ENI.
- A secondary private IP can be bound and unbound.
Elastic IP
Bind each of the private IP addresses on the ENI.
Security Group
An ENI can be bound to one or more security groups.
MAC address
The ENI has a globally unique MAC address.