Step 4: Add an SNAT Rule

Scenarios

After a public NAT gateway is created, add SNAT rules for it. With SNAT rules, servers that are connected to a VPC using Direct Connect can access the Internet by sharing an EIP.

Each SNAT rule is configured for only one CIDR block. If servers that are connected to a VPC using Direct Connect are in multiple CIDR blocks, you can create multiple SNAT rules to allow the servers to share EIPs.

Prerequisites

A public NAT gateway is available.

Procedure

1. Log in to the management console.

2. Click in the upper left corner and select the desired region and project.
3. Click Service List in the upper left corner. Under Networking, select NAT Gateway.

   The Public NAT Gateway page is displayed.

4. On the displayed page, click the name of the public NAT gateway on which you need to add an SNAT rule.
5. On the SNAT Rules tab, click Add SNAT Rule.
   Figure 1 Add SNAT Rule
   

6. Configure required parameters. For details, see Table 1.

   Table 1 Descriptions of SNAT rule parameters

   Parameter	Description
   Scenario	Select Direct Connect/Cloud Connect if your on-premises servers or servers in another VPC need to access the Internet.
   CIDR Block	The CIDR block of the servers in the on-premises data center or in another VPC
   EIP	The EIP used for accessing the Internet You can select an EIP that either has not been bound, has been bound to a DNAT rule of the current public NAT gateway with Port Type set to Specific port, or has been bound to an SNAT rule of the current public NAT gateway. You can select up to 20 EIPs for an SNAT rule. If you have selected multiple EIPs for an SNAT rule, one EIP will be chosen randomly.
   Monitoring	You can create alarm rules on the Cloud Eye console to monitor your SNAT connections and keep informed of any changes in a timely manner.
   Description	Provides supplementary information about the SNAT rule. Enter up to 255 characters. Angle brackets (<>) are not allowed.

7. Click OK.
8. View details in the SNAT rule list.
   If Status of the SNAT rule is Running, the SNAT rule has been created.

   

   • You can add multiple SNAT rules for a public NAT gateway to suite your service requirements.
   • Each VPC can be associated with multiple public NAT gateways.
   • Only one SNAT rule can be added for each VPC subnet.