Configuring Region Lines

Background

Usually, a DNS server returns the same resolution result to all visitors, irrespective of where they come from. In cross-region access, this would lead to long latency and poor user experience.

If you configure region lines when you create record sets, the DNS server returns different resolution results or IP addresses to visitors based on their locations.

Region lines can be used only in public zones. You cannot specify region lines in private zones or PTR records.

For example, you have built a website using domain name example.com and hosted the website on two servers, one in Chinese mainland and the other in another region or country. You need to configure three lines: Default, Chinese mainland, and Global.

Region Lines

Region lines are categorized by geographic areas, as shown in Table 1.

Chinese mainland is an Asia-Pacific region. To facilitate your selection of Chinese Mainland lines, Chinese mainland lines are displayed separately.

For example, you have configured the following resolution lines for record set example.com:

• Default: 1.1.1.1
• Chinese mainland: 2.2.2.2
• Global_Hong Kong (China): 3.3.3.3

When a user in Shanghai requests the domain name example.com, IP address 2.2.2.2 is returned. When a user in Hong Kong requests this domain name, IP address 3.3.3.3 is returned. When a user in New Zealand requests this domain name, IP address 1.1.1.1 is returned.

Procedure

Configure region lines for your public domain names hosted on the DNS service.

The following example describes how to configure the record set of the Default line to 1.1.1.1 and the record set of the Global_Hong Kong (China) line to 2.2.2.2 for example.com.

1. Log in to the management console.
2. Hover the cursor over in the upper left corner. In the service list, choose Networking > Domain Name Service.

   The DNS console is displayed.

3. In the navigation pane on the left, choose Public Zones.

   The Public Zones page is displayed.

4. On the Public Zones page, click the domain name (example.com) of the public zone.

   The Record Sets page is displayed.

5. Click Add Record Set.

   The Add Record Set dialog box is displayed.

   Figure 1 Add Record Set
   

6. Add two A record sets for example.com. Set the parameters based on Table 2.

   Table 2 Parameters for adding an A record set

   Parameter	Description	Line 1	Line 2
   Name	Prefix of the domain name to be resolved. For example, if the domain name is example.com, the prefix can be as follows: www: The domain name is www.example.com, which is usually used for a website. Left blank: The domain name is example.com. In some cases, you may need to set the record set name to the at sign (@). However, the at sign is not supported. Leave the Name blank. abc: The domain name is abc.example.com, a subdomain of example.com. mail: The domain name is mail.example.com, which is typically used for an email server. *: The domain name is *.example.com, which is a wildcard domain name, indicating all subdomains of example.com.	www	www
   Type	Type of the record set	A – Map domains to IPv4 addresses	A – Map domains to IPv4 addresses
   Line	The DNS server will return the IP address of the specified line, depending on where the visitors come from. Default: returns the default resolution result irrespective of where the visitors come from. ISP: returns the resolution result based on visitors' carrier networks. For details, see Configuring ISP Lines. Region: returns the resolution result based on visitors' geographical locations.	Default	Select Region and Global_Asia Pacific_Hong Kong (China)
   TTL (s)	Cache duration of the record set on a local DNS server, in seconds. The value ranges from 300 to 2147483647, and the default is 300. If your service address changes frequently, set TTL to a smaller value. Learn more about TTL.	The default value is 300s, which is, 5 minutes.	The default value is 300s, which is, 5 minutes.
   Value	IPv4 addresses mapped to the domain name Every two IPv4 addresses are separated using a line break.	1.1.1.1	2.2.2.2
   Weight	(Optional) Weight of a record set. The value ranges from 0 to 1000, and the default value is 1. This parameter is supported only for public domain names. If a resolution line in a zone contains multiple record sets of the same type, you can set different weights to each record set. For details, see Configuring Weighted Routing.	1	1
   Tag	(Optional) Identifier of the record set. This parameter is displayed when you expand More Settings. Each tag contains a key and a value. You can add a maximum of 10 tags to a record set. For details about tag key and value requirements, see Table 3.	example_key1 example_value1	example_key1 example_value1
   Description	(Optional) Supplementary information about the record set. You can enter a maximum of 255 characters.	N/A	N/A

   Table 3 Tag key and value requirements

   Parameter	Requirements	Example Value
   Key	Cannot be left blank. Must be unique for each resource. Can contain a maximum of 36 characters. Cannot start or end with a space or contain special characters =*<>\,|/	example_key1
   Value	Cannot be left blank. Can contain a maximum of 43 characters. Cannot start or end with a space or contain special characters =*<>\,|/	example_value1

7. Click OK.