A public zone contains information about how a domain name (for example, www.example.com) and its subdomains are translated into IP addresses, like 1.2.3.4, for routing traffic over the Internet. Visitors can access your website or web application by entering your domain name in the address box of their browser.

Routing Internet Traffic to a Website

You can retrieve a public zone that has been created by another user.

A private zone contains information about how to map a domain name (such as ecs.com) and its subdomains used within one or more VPCs to private IP addresses (such as 192.168.1.1). With private domain names, your ECSs can communicate with each other within the VPCs without having to connect to the Internet. These ECSs can also access cloud services, such as OBS and SMN, over a private network.

If you have deployed ECSs and other cloud services, you can configure private domain names for the ECSs so that they can communicate with each other or access the cloud services over a private network.

Routing Traffic Within VPCs

Reverse resolution is when you obtain a domain name based on an IP address. This is typically used to affirm the credibility of email servers.

After a recipient server receives an email, it checks whether the IP address and domain name of the sender server are trustworthy, to help identify spam. If the recipient server cannot obtain the domain name mapped to the IP address of the sender server, the email considered malicious and rejected. It is necessary to configure pointer records (PTR) to point the IP addresses of your email servers to domain names.

Creating a PTR Record

Usually, a DNS server returns the same resolution result to all visitors, irrespective of where they come from. When cross-region access is involved, this means excessive 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.

Configuring ISP Lines

Configuring Region Lines

Configuring Custom Lines

Configuring Weighted Routing

DNS provides REST APIs.

You can access all DNS functions through convenient APIs, functions including creating, querying, modifying, and deleting public zones, private zones, and record sets.

Available in all regions

API Overview

DNS also provides SDKs for you to easily call DNS APIs.

SDKs support Java, Python, Go, and .NET languages. You can use APIs or any other well-known SDKs.

Available in all regions

SDK Overview