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Last Updated: Sep 13, 2018

Secondary DNS is a DNS backup service provided for users who use their own or a third-party managed DNS.

You can use Alibaba Cloud DNS to back up your existing DNS, whether it is managed on-premise or through another managed service provider. If your primary DNS suffers an outage, Alibaba Cloud DNS can keep your business online and ensure you can still provide a global DNS solution to your customers.

When you enable Secondary DNS, Alibaba Cloud DNS is used as the secondary DNS by default, and your existing DNS is the primary DNS. The secondary DNS and primary DNS communicate with each other using a regional data transmission mechanism based on RFC standard protocols. Resource record changes in the primary DNS are automatically synchronized to the secondary DNS. When a fault occurs with your primary DNS, the secondary DNS is used to provide the same service to your customers and ensure quick access to your service.

Note: When Secondary DNS is enabled, all resource records are synchronized with your primary DNS. You cannot manually modify the records in the secondary DNS.

To enable Secondary DNS, make sure your DNS server supports standard RFC protocols such as XFR and NOTIFY. Alibaba Cloud DNS is compatible with BIND 9.1.0 and later versions. We recommend that you use the recommended DNS servers. The following section uses the BIND DNS server as an example. For more information about how to enable Secondary DNS on other DNS servers, continue reading.


  • Back up existing DNS

    Secondary DNS backs up all of your existing DNS files. When exceptions occur to your existing DNS, Alibaba Cloud DNS provides domain name service to your customers and keeps your service running across the globe.

  • Stable and reliable

    Alibaba Cloud DNS offers high availability and significantly improves the availability of your DNS service.

  • Global deployment

    Based on Alibaba Cloud global network infrastructure, Alibaba Cloud DNS enhances the speed of worldwide DNS queries and ensures that your customers are readily served wherever they are.

  • Security assurance

    With Secondary DNS, you can choose to hide the primary DNS and use the secondary DNS to handle all DNS queries. This guarantees the security of the primary DNS, and takes full advantage of the security mechanisms provided by Alibaba Cloud DNS.


Secondary DNS can be used by users who host their own DNS internally, or at another managed DNS provider. If you use your own DNS service, make sure your DNS provider supports the Secondary DNS service.

Currently, Secondary DNS is in beta testing and only available to paying users. No fees will be charged for Alibaba Cloud Advanced DNS users. After beta is closed, we will notify you one month in advance before the product is released and a new billing method is applied.