Before you use elastic IP addresses (EIPs), make sure that you understand the limits.

General limits

  • You can apply for at most 20 EIPs with each Alibaba Cloud account.

    You can increase the quota on the Quota Management page. For more information, see Manage quotas.

  • You can associate an EIP only with one cloud resource. The EIP that you want to associate must be in the Available state. After you associate an EIP with a cloud resource, the EIP immediately takes effect.
  • If an EIP is locked for security reasons, you cannot release the EIP, associate the EIP with a cloud resource, or disassociate the EIP from a cloud resource.
  • The following table describes the bandwidth limits on EIPs.
    Pay-by-data-transfer EIP Pay-by-bandwidth EIP
    The maximum bandwidth of a pay-by-data-transfer EIP cannot be higher than 200 Mbit/s. This value indicates the upper limit of bandwidth usage. The maximum bandwidth is only for reference and is not a guaranteed value. In scenarios of resource contention, the maximum bandwidth may not be reached. The maximum bandwidth of a pay-by-bandwidth EIP cannot be higher than 500 Mbit/s. The maximum bandwidth is a guaranteed value. In scenarios of resource contention, the maximum bandwidth can be reached.
    For each Alibaba Cloud account, the sum of the peak bandwidth of all pay-by-data-transfer EIPs in a region cannot exceed 5 Gbit/s. If your business requires guaranteed bandwidth or larger bandwidth, you can purchase pay-by-bandwidth EIPs. For each Alibaba Cloud account, the sum of the peak bandwidth of all pay-by-bandwidth EIPs in a region cannot exceed 50 Gbit/s. You can contact the product manager from Alibaba Cloud to increase the quota.
  • The following limits apply to the inbound and outbound bandwidth for EIPs that were purchased after 00:00 (UTC+8) on February 15, 2020:
    • Inbound bandwidth (data is transferred to EIPs)
      • If the maximum bandwidth of the EIP that you purchased is equal to or higher than 10 Mbit/s, the inbound bandwidth allocated to the EIP equals the maximum bandwidth of the EIP.
      • If the maximum bandwidth of the EIP that you purchased is lower than 10 Mbit/s, the inbound bandwidth allocated to the EIP is 10 Mbit/s.
    • Outbound bandwidth (data is transferred from EIPs)

      The outbound bandwidth allocated to an EIP equals the maximum bandwidth of the EIP.

  • The following limits are imposed when you configure Anti-DDoS protection for EIPs:
    • Only pay-as-you-go EIPs support Anti-DDoS Pro/Premium.
    • To use Anti-DDoS Pro/Premium, you must associate the EIP with an EIP bandwidth plan that also has Anti-DDoS Pro/Premium enabled.
    • You can enable Anti-DDoS Pro/Premium only when you purchase an EIP. After you purchase an EIP with Anti-DDoS Origin enabled, you cannot upgrade Anti-DDoS Origin to Anti-DDoS Pro/Premium.
    • After you enable Anti-DDoS Pro/Premium for an EIP, you cannot disable Anti-DDoS Pro/Premium.

Limits on associating an EIP with an Elastic Compute Service (ECS) instance

  • The ECS instance must be deployed in a virtual private cloud (VPC).
  • The ECS instance and the EIP must belong to the same region.
  • The ECS instance must be in the Running or Stopped state.
  • The ECS instance is not assigned a static public IP address or an EIP.
  • Each ECS instance can be associated only with one EIP. If you want an ECS instance to use multiple EIPs, you can attach secondary elastic network interfaces (ENIs) that are associated with EIPs to the ECS instance.
    • Associate an EIP with each secondary ENI. Then, attach the secondary ENIs to the ECS instance. The number of secondary ENIs that can be attached to an ECS instance varies based on the specification of the ECS instance. For more information, see Instance family.
    • Associate multiple EIPs with a secondary ENI in NAT mode. In this mode, each EIP is associated with a secondary private IP address of the secondary ENI. Then, associate the secondary ENI with the ECS instance. For more information, see Associate multiple EIPs with an ECS instance in NAT mode.

Limits on associating an EIP with a NAT gateway

  • The NAT gateway and the EIP must belong to the same region.
  • You can associate at most 20 EIPs with a NAT gateway. You can associate at most 10 pay-by-data-transfer EIPs with a NAT gateway.

    You can increase the quota on the Quota Management page. For more information, see Manage quotas.

Limits on associating an EIP with a Server Load Balancer (SLB) instance

  • The SLB instance must be deployed in a VPC.
  • The SLB instance and the EIP must belong to the same region.
  • You can associate only one EIP with each SLB instance.

Limits on associating an EIP with a high-availability virtual IP address (HAVIP)

  • The HAVIP and the EIP must belong to the same region.
  • The HAVIP must be in the Available or Allocated state.
  • You can associate only one EIP with each HAVIP.

Limits on associating an EIP with a secondary ENI

  • The secondary ENI must be deployed in a VPC.
  • The secondary ENI and the EIP must belong to the same region.
  • You can associate an EIP with a secondary ENI in NAT mode or cut-through mode.
    • The number of EIPs that you can associate with a secondary ENI in NAT mode depends on the number of private IP addresses of the secondary ENI.
    • You can associate only one EIP with a secondary ENI in cut-through mode.