NAT Gateway：CreateSnatEntry

The region ID of the NAT gateway.

You can call the DescribeRegions operation to query the most recent region list.

Valid values:

• ap-northeast-2-pop

  :

  ap-northeast-2-pop

  .

The ID of the SNAT table.

The ID of the vSwitch.

• When you add an SNAT entry to an Internet NAT gateway, this parameter specifies that ECS instances in the vSwitch can use the SNAT entry to access the Internet. If you select multiple elastic IP addresses (EIPs) to create an SNAT address pool, connections are hashed to these EIPs. Network traffic may not be evenly distributed to the EIPs because the amount of traffic that passes through each connection varies. We recommend that you associate these EIPs with the same EIP bandwidth plan to prevent service interruptions due to the bandwidth limits on individual EIPs.
• When you add an SNAT entry to a VPC NAT gateway, this parameter specifies that ECS instances in the vSwitch can use the SNAT entry to access external networks.

You can specify the CIDR block of a VPC, a vSwitch, or an ECS instance or enter a custom CIDR block.

You can specify an SNAT entry in the following ways:

• You can specify the CIDR block of the VPC where the NAT gateway is deployed. Then, all ECS instances in the VPC can access the Internet or external networks by using SNAT.
• You can specify the CIDR block of a vSwitch, for example, 192.168.1.0/24. Then, the ECS instances in the vSwitch can access the Internet or external networks by using SNAT.
• You can specify the IP address of an ECS instance, for example, 192.168.1.1/32. Then, the ECS instance can access the Internet or external networks by using SNAT.
• You can specify a custom CIDR block. Then, all ECS instances within the specified CIDR block can access the Internet or external networks by using SNAT.

When you add an SNAT entry to an Internet NAT gateway, if SnatIp is set to an EIP, the ECS instance uses the specified EIP to access the Internet.

If SnatIp is set to multiple EIPs, the ECS instance randomly selects an EIP specified in the SnatIp parameter to access the Internet.

You cannot specify this parameter and SourceVSwtichId at the same time. If SourceVSwitchId is specified, you cannot specify SourceCIDR. If SourceCIDR is specified, you cannot specify SourceVSwitchId.

• The EIPs in the SNAT entry when you add an SNAT entry to an Internet NAT gateway. Separate EIPs with commas (,).

• When you add SNAT entries for a VPC NAT gateway, this parameter specifies the NAT IP addresses in the SNAT entry. Separate multiple NAT IP addresses with commas (,).

The name of the SNAT entry.

The name must be 2 to 128 characters in length. It must start with a letter but cannot start with http:// or https://.

The client token that is used to ensure the idempotence of the request.

You can use the client to generate the token, but you must make sure that the token is unique among different requests. The client token can contain only ASCII characters.

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Description If you do not specify this parameter, the system automatically uses the request ID as the client token. The request ID may be different for each request.

Specifies whether to enable EIP affinity. Valid values:

• 0: no
• 1: yes

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Description After you enable EIP affinity, if multiple EIPs are associated with an SNAT entry, each client uses one EIP to access the Internet. If EIP affinity is disabled, each client uses a random EIP to access the Internet.