Importing and Exporting DNAT Rules Using Templates

Scenarios

After a NAT gateway is created, you can add DNAT rules to allow servers in your VPC to provide services accessible from the Internet.

You can configure a DNAT rule for each port of a server. If multiple servers need to provide services accessible from the Internet, you need to create multiple DNAT rules.

Prerequisites

A NAT gateway has been created.

Procedure

1. Log in to the management console.
2. Under Network, click NAT Gateway.
3. On the displayed page, click the name of the NAT gateway for which you want to add the DNAT rule.
4. On the NAT gateway details page, click the DNAT Rules tab.
5. On the displayed page, click Import Rule and then Download Template.
6. Fill in DNAT rule parameters based on the table heading in the template. For details, see Table 1.

   Table 1 Parameter description

   Parameter	Description
   Scenario	VPC: indicates that the servers in a VPC can share one EIP to provide services accessible from the Internet through the DNAT rule. Direct Connect: indicates that servers in your data center that are connected to a VPC using Direct Connect or VPN can provide services accessible from the Internet through the DNAT rule.
   Port Type	Specifies the port type, including All ports and Specific port. All ports: indicates the IP mapping method. This method is equivalent to assigning an EIP to a server. Any requests on the EIP will be forwarded by the NAT gateway to your server based on IP address mapping. Specific port: indicates the port mapping method. The NAT gateway forwards the requests with specific protocol and port on the EIP to the corresponding port of the target server.
   Protocol	The protocol can be TCP or UDP. This parameter is available if you select Specific port for Port Type. If you select All ports, the value of this parameter will be All by default.
   EIP	Specifies the EIP that will be used by the server to provide services accessible from the Internet. Only EIPs that have not been bound or that have been bound to a DNAT rule in the current VPC are available for selection.
   Outside Port	Specifies the EIP port. This parameter is available if you select Specific port for Port Type. The value can be a single port number or a port range, for example, 80 or 80-100.
   Private IP Address	In the VPC scenario, set this parameter to the IP address of the server in a VPC. This IP address is used by the server to provide services accessible from the Internet through DNAT. In the Direct Connect scenario, set this parameter to the IP address of the server in the local data center or the user's private IP address. This IP address is used by local servers that are connected to a VPC through Direct Connect or VPN to provide services accessible from the Internet through DNAT.
   Inside Port	In the VPC scenario, set this parameter to the port of the server in a VPC. In the Direct Connect scenario, set this parameter to the port of the server in the local data center or the user's private port. This parameter is available if you select Specific port for Port Type. The number of inside and outside ports must match.

7. After filling in the template, click Import Rule, select the template, and click Import.
   Figure 1 Import Rule
   
8. View details in the DNAT rule list. If Status is Running, the rules have been added successfully.
9. On the DNAT Rules tab page, click Export Rule to export the configured DNAT rule template.