Public DNS

What is Public DNS?

DNSPod, as the largest third-party authoritative DNS service provider in China, has discovered more and more DNS resolution problems in the process of providing authoritative DNS service for a high number of domain names, such as the established reliance on authoritative DNS as the internet infrastructure. With continuous growth, the existing DNS systems have also started seeing more and more problems, such as increasing DNS attacks, severe DNS hijacking in the local DNS of ISPs, cross-network DNS resolution results caused by NAT, and low stability. The original authoritative DNS service of DNSPod could no longer solve these problems perfectly.
DNSPod has accumulated lots of DNS-related technologies and resources. Only providing authoritative DNS service cannot better serve all users.
Therefore, DNSPod launched a public DNS service: Public DNS, with the aim to solve the DNS resolution problems for all users. User feedback is welcome for the purpose of continuous service improvement.

Who can use Public DNS?

Public DNS is a public recursive DNS service provided by DNSPod. Anyone who can modify their DNS configuration can use it. For more information, please see Access Guide.

What is the structure of Public DNS?

Public DNS has deployed first-level cache DNS cluster nodes in three places in Mainland China, where each node implements layer-4 load balancing (round-robin DNS) through multiple 10-Gigabit servers. The same service IP 119.29.29.29 is used uniformly across all nodes, which achieve peering connection with the top 16 ISPs in Mainland China based on BGP AnyCast technology to ensure nearby access for users. The first-level cache is responsible for receiving and answering users' DNS query requests and forwarding domains that miss the cache to the second-level cache for query.
The second-level cache is responsible for receiving the DNS query requests forwarded by the first-level cache, forwarding them to the corresponding backend recursive nodes according to the user IP, receiving DNS responses from the recursive nodes, and returning them to the first-level cache. In addition, it provides cache services for multiple first-level cache servers to reduce the pressure on the backend recursive nodes and improve the response speed.
Backend recursive nodes are deployed in the split zones of ISPs in various provinces. If the authoritative DNS of the domain supports the ECS protocol, more accurate DNS resolution can be provided. An ISP in a province where no recursive nodes are deployed will preferably schedule DNS requests to the same ISP in the neighboring province for resolution.
The primary cache, secondary cache, and recursive DNS are all proprietary high-performance DNS resolution programs and support the ECS protocol, which guarantees a fast, accurate, and stable DNS service for users.