Tenant Cloud Network NAT Gateway Operation Guide

Managing NAT Gateway EIPs

Last Updated At: 2025-10-29 17:57:02

After creating a NATGW, you can manage the EIPs of the NATGW. The following section describes the management method in detail.

  1. Log in to the VPC console.
  2. In the left directory, click NATGW to go to the NATGW List page.
  3. Click a gateway ID in the list to go to the details page.
  4. Select the EIP Association tab, on which you can choose to bind or unbind an EIP.

Bind an EIP

Note:

When a NATGW is bound to multiple EIPs, the system automatically performs load balancing.

Click Bind EIP, select the EIP to be bound in the dropdown list, and click Save.

Unbinding an EIP

Note:

A NATGW should be bound to at least one EIP.

In the Operation column of the EIP that needs to be unbound, click Unbind.

Setting Active/Standby EIPs

Note:
  • When a NATGW is bound to only one EIP, it does not support setting a standby IP. When a NATGW is bound to two or more EIPs, it supports setting a standby IP.
  • Multiple active EIPs and only one standby EIP can be set.
  1. In the Operation column of the line where the corresponding EIP is located, click Set to Standby IP.
  2. Click OK in the pop-up box to complete the standby IP settings.
  3. When you no longer need a standby IP, you can restore the EIP to the active IP. In the Operation column of the EIP, click Restore to Active IP.
  4. Click OK in the pop-up box to complete the active IP restoration.

Actual Forwarding Logic of Active/Standby EIPs

EIPs have corresponding health detections. When the health of the active EIP is detected to be abnormal:

  • If there are EIPs in standby status and the number of available EIPs is greater than or equal to 1, data plane forwarding will be stopped for the abnormal EIP. An "(Abnormal)" suffix will be added to the abnormal EIP, while the processing logic and suffix of the original EIP in the "Standby" status remain unchanged.
  • If there are EIPs in standby status and the number of available EIPs is zero, data plane forwarding will be stopped for the abnormal EIP. An "(Abnormal)" suffix will be added to the abnormal EIP, while the data plane of the original EIP in the "Standby" status will start forwarding, and its suffix will change to "(Standby, in use)".

When the active EIP is recovered:

  • The data plane of the active EIP resumes forwarding first, then the standby EIP stops data plane forwarding, and the suffix is restored to its original status.