Attaches an EIP to a cloud product instance in the same region.

Note the following when you call this action:
  • You can attach an EIP to a VPC ECS instance, a VPC SLB instance, or a NAT Gateway in the same region.
  • To attach an EIP to a NAT Gateway, make sure that there was no NAT bandwidth package under your account before January 26, 2018. Otherwise open a ticket to attach the EIP to the NAT Gateway.


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Request parameters

Parameter Type Required? Example value Description
Action String Yes AssociateEipAddress

The name of this action. Value:


AllocationId String Yes eip-2zeerraiwb7uj6i0d0fo3

The ID of the EIP.

InstanceId String Yes i-2zebb08phycz6pok9xwe

The ID of the instance to attach.

RegionId String Yes cn-hangzhou

The ID of the region to which the EIP belongs.

InstanceRegionId String No cn-hangzhou

The ID of the region to which the attached instance belongs.

InstanceType String No EcsInstance

The type of the cloud product instance to attach.

Valid values:Nat | SlbInstance | EcsInstance | NetworkInterface

PrivateIpAddress String No

An IP address in the CIDR block of the VSwitch.

If you leave the option empty, the system allocates a private IP address according to the VPC ID and VSwitch ID.

Response parameters

Parameter Type Example value Description
RequestId String C0FD0EED-F90D-4479-803D-DD62335357E5 The ID of the request.


Request example

Response example
  • XML format

  • JSON format


Error codes

HTTP status code Error code Error message Description
400 InvalidAssociation.Duplicated Specified instance already is associated. This instance is already attached to an EIP or Global Acceleration instance. You must delete this instance before you can attach it to a different EIP or Global Acceleration instance.
400 OperationDenied Specified instance is not in VPC. The specified instance does not exist in the VPC.
400 InvalidParameter.Mismatch Specified elastic IP address and ECS instance are not in the same region. The specified EIP and ECS instances are not in the same region.
400 IncorrectEipStatus Current elastic IP status does not support this operation The current status of the specified EIP address does not support this operation.
404 InvalidInstanId.NotFound Specified instance does not exist. The specified instance does not exist.
400 IncorrectInstanceStatus Current instance status does not support this operation. The current instance status does not support this operation.
400 InvalidInstanceType.ValueNotSupported The specified value of InstanceType is not supported. The value of the InstanceType parameter is invalid.
400 IncorrectHaVipStatus HaVip can be operated by this action only when it's status is Available or InUse. You can perform this operation only if the HAVIP is the Available or InUse state.
400 InvalidParameter The specified parameter is not valid. The specified parameter value is invalid.
400 OperationDenied Eip of default vpc not allow this operation The EIP of the default VPC does not support this operation.
400 Forbbiden The eip instance owener error You need to be authorized to call the EIP. Please check that you have the appropriate permissions and try again.
400 InvalidBindingStatus The eip binding status invalid. The attaching status of the EIP is invalid.
400 BIND_INSTANCE_HAVE_PORTMAP_OR_BIND_EIP The instance may have portMap or already bind eip. You must delete the existing port forwarding rule associated with the ECS instance first.
400 BIND_INSTANCE_OWENER_ERROR Cannot operate the eip. You cannot operate this EIP.
404 InvalidAllocationId.NotFound Specified allocation ID is not found The specified public IP address does not exist.

See common error codes