Overview

Application Scenarios

You can bind an EIP to an ECS to enable the ECS to access the Internet. If you want to change an EIP for an ECS, you need to unbind the current EIP from the ECS first.

• If there is no EIP, assign one.
• If you have released EIPs, the system preferentially assigns EIPs from the ones you released in the last 24 hours.

  If you do not want an EIP that you have released, it is recommended that you buy another EIP first and then release the one that you do not want.

  For details, see What Is the EIP Assignment Policy?

Architecture

In this example, ECS-A, EIP-A, and EIP-B are in region A, and EIP-A is bound to ECS-A. To bind EIP-B to ECS-A, you need to:

1. Unbind EIP-A from ECS-A.
2. Bind EIP-B to ECS-A.
   Figure 1 Changing EIP
   

Notes and Constraints

• Each EIP can be bound to only one cloud resource and they must be in the same region.
• An EIP and its bound cloud resource can use different billing modes.

  For example, a yearly/monthly EIP can be bound to a pay-per-use ECS.

• If you need to bind or unbind an EIP that is frozen due to account arrears or for security reasons, you need to unfreeze the EIP first. For details, see