1. What is the difference between an EIP and a public IP address of an ECS instance?

  • A public IP can be found on the private NIC of the ECS instance, while an EIP is a NAT IP that is mapped to the private NIC of the ECS instance. Therefore, the EIP cannot be found on the NIC of the ECS instance.

  • You cannot unbind a public IP from the ECS instance but you can bind and unbind an EIP whenever Internet communication is not needed.

2. Why cannot I find an EIP on the private NIC?

An EIP is configured on the Internet gateway and mapped to the private NIC of the ECS instance. Therefore, it cannot be found on the private NIC.

3. How many EIPs can an account create?

An account can create 20 EIPs at most. Open a ticket if you want to apply for more.

4. What resources can an EIP be bound to?

An ECS or SLB instance of the VPC network, or a NAT Gateway.

5. Can an EIP be bound to an ECS instance of the classic network?

No.

6. Why cannot I access an EIP I have created?

  • The EIP is not bound to any resources.
  • If the EIP is bound to an ECS instance, check the security rules of the ECS instance. For example, if the ECS instance is added to a security group that denies the access from port 80, then you cannot access the EIP over port 80.
  • Check if payment for the EIP is overdue.

7. Why cannot I bind an EIP to an ECS instance?

  • Check the network type of the ECS instance. An EIP can only be bound to an ECS instance of the VPC network.
  • The regions of the EIP and ECS instance are not the same.
  • The ECS instance is not running or stopped.
  • The ECS instance has been bound to an EIP.
  • The ECS instance has a public IP that is system allocated.

8. Why cannot I bind an EIP to a NAT Gateway?

If you purchased a NAT bandwidth package before January 26, 2018, you still need to use the NAT bandwidth package to provide public IPs for the NAT Gateway. To bind an EIP, open a ticket.