This topic describes the limits on NAT Gateway and how to increase quotas.
Limits on NAT gateways
|The maximum number of enhanced NAT gateways that can be created for a virtual private cloud (VPC)||5||Submit a ticket.|
|The maximum number of standard NAT gateways that can be created for a VPC||1||N/A|
|The maximum number of elastic IP addresses (EIPs) that can be associated with a NAT gateway||20. You can associate up to 10 pay-by-data-transfer EIPs with a NAT gateway.|
|The maximum number of pay-by-data-transfer EIPs that can be associated with a NAT gateway||10|
|Creating a NAT gateway for a VPC that contains a custom route entry whose destination CIDR block is 0.0.0.0/0||
Limits on SNAT
|The maximum number of Source Network Address Translation (SNAT) entries that can be added to a NAT gateway||40|
|The maximum number of EIPs that can be specified in a SNAT entry||64||N/A|
|Limits on a vSwitch by the bandwidth limit of the EIPs in the SNAT entry that is added to the vSwitch||Yes
Note If the EIPs are added to an EIP bandwidth plan, the bandwidth of the vSwitch is limited by the bandwidth limit of the EIP bandwidth plan.
|The maximum number of concurrent connections is limited by the number of EIPs specified in the SNAT entry||Elastic Compute Service (ECS) instances in a VPC may access the same destination IP
address and port on the Internet by using a NAT gateway. If static public IP addresses
or EIPs are not associated with the ECS instances, the maximum number of concurrent
connections that the NAT gateway supports is based on the number of EIPs in the SNAT
|The bandwidth limit of each EIP in a SNAT entry||If you select multiple EIPs to create a SNAT IP address pool, make sure that you associate
these EIPs with the same EIP bandwidth plan.
For more information, see Create a SNAT IP address pool.
- Change the bandwidth limit from a value that is smaller than 1 Gbit/s to a value that is larger than 1 Gbit/s.
- Change the bandwidth limit from a value that is larger than 1 Gbit/s to a value that is smaller than 1 Gbit/s.
We recommend that you enable automatic reconnection for your workloads to minimize the impact of service interruptions.
Limits on DNAT
|The maximum number of DNAT entries that can be added to a NAT gateway||100|
|Creating DNAT entries for ECS instances with which EIPs are associated||Not supported.
Before you can create DNAT entries for the ECS instances, disassociate the EIPs from the ECS instances. For more information, see Disassociate an EIP from a cloud resource and Create a DNAT entry to provide Internet-facing services.
Note If you add DNAT entries to an ECS instance with which an EIP is associated, the ECS instance preferably uses the EIP to communicate with the Internet.