Limits

Quota

Item	Default	Adjustable
Pay-as-you-go EIPs per account (excludes subscription EIPs)	20	Request an increase on the Quota Management page or in Quota Center.

Association limits

General

One resource — Each EIP can be associated with only one cloud resource at a time.
Security lock — If an EIP is locked for security reasons, you can't associate, disassociate, or release it.
Region — The EIP and the target resource must be in the same region.

ECS instance

Instance state — The Elastic Compute Service (ECS) instance must be Running or Stopped.
Existing public IP — The ECS instance can't already have a static public IP address or another EIP.
EIPs per instance — One EIP per ECS instance. For multiple EIPs, attach secondary ENIs and bind an EIP to each. You can also associate multiple EIPs with an ECS instance in NAT mode.

Internet NAT gateway

EIPs per gateway — Up to 20 EIPs per internet NAT gateway.

Since September 19, 2022, associating an EIP with a new internet NAT gateway consumes one private IP address from the gateway's vSwitch. Ensure the vSwitch has available private IP addresses. Existing NAT gateways are not affected.

CLB instance

EIPs per instance — One EIP per Classic Load Balancer (CLB) instance.

HaVip

High-availability virtual IP address (HaVip) state — The HaVip must be Available or Allocated.
EIPs per HaVip — One EIP per HaVip.

Elastic Network Interface (ENI)

Association mode:

NAT mode: the number of EIPs depends on how many private IP addresses the ENI has.
Cut-through mode: one EIP only.

Bandwidth limits

	Pay-by-data-transfer EIP	Pay-by-bandwidth EIP
Max bandwidth per EIP	200 Mbit/s (best-effort — not guaranteed under contention)	500 Mbit/s (guaranteed, even under contention)
Aggregate bandwidth per region per account	5 Gbit/s across all pay-by-data-transfer EIPs in the region. For guaranteed or higher bandwidth, use pay-by-bandwidth EIPs.	50 Gbit/s across all pay-by-bandwidth EIPs in the region. Contact your account manager to raise this limit.

When a pay-by-data-transfer EIP is associated with an Internet Shared Bandwidth instance, the EIP's billing method and bandwidth cap no longer apply. The Internet Shared Bandwidth instance governs both billing and bandwidth.

Inbound and outbound bandwidth

These limits apply to EIPs purchased after 00:00:00 (UTC+8), February 15, 2020:

Inbound bandwidth (traffic into the EIP):

If the max bandwidth is 10 Mbit/s or higher, inbound bandwidth equals the max bandwidth.
If the max bandwidth is below 10 Mbit/s, inbound bandwidth is 10 Mbit/s.

Outbound bandwidth (traffic out of the EIP): Equals the max bandwidth.

Anti-DDoS protection limits

Anti-DDoS (Enhanced) is only available for pay-as-you-go BGP (Multi-ISP) EIPs.
To create an Anti-DDoS (Enhanced) EIP from an IP address pool, the pool must also be Anti-DDoS (Enhanced).
You set the protection type when you create the EIP. You can't change it later.
Regions where Anti-DDoS (Enhanced) is available:
EIP
- China: China (Beijing), China (Hangzhou), China (Shanghai), and China (Hong Kong)
- Asia Pacific: Philippines (Manila), Japan (Tokyo), Singapore, Malaysia (Kuala Lumpur), Indonesia (Jakarta), South Korea (Seoul), and Thailand (Bangkok)
- Others: US (Virginia), US (Silicon Valley), Germany (Frankfurt), UK (London), and Mexico
IP address pool
- China: China (Hong Kong)
- Asia Pacific: Philippines (Manila), Japan (Tokyo), Singapore, Malaysia (Kuala Lumpur), Indonesia (Jakarta), South Korea (Seoul), and Thailand (Bangkok)
- Others: US (Virginia), US (Silicon Valley), Germany (Frankfurt), UK (London), and Mexico

Cross-region access

ECS instances with EIPs in China (including Hong Kong and Macao, but excluding Taiwan) may see high latency and packet loss when reaching ECS instances in other regions. Use Cloud Enterprise Network (CEN) for cross-region connections instead.