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Alibaba Cloud DNS:Public Zone supports blacklist and whitelist

Last Updated:Jun 02, 2026

Use the blacklist and whitelist feature to control which domains Public DNS resolves for your application.

Use cases

Public DNS, which includes HTTPDNS, is designed for mobile clients such as apps and IoT devices. Unlike ISP Local DNS, Public DNS routes resolution requests directly, bypassing ISP infrastructure to prevent domain hijacking, accelerate domain name resolution, and improve scheduling accuracy based on the client's source IP address.

Configure a blacklist, a whitelist, or both when you need precise control over domain resolution in your application:

  • Block specific domains: Add domains to the blacklist to prevent resolution, regardless of whitelist settings.

  • Allow only approved domains: Configure a whitelist to restrict resolution to explicitly permitted domains.

  • Combine both lists: Use the blacklist and whitelist together for granular control within a defined set of allowed domains.

How it works

Public DNS evaluates each resolution request against your blacklist and whitelist. The blacklist always takes precedence: a domain on the blacklist is blocked even if it also appears on the whitelist.

Whitelist

Blacklist

Resolution behavior

Empty

Empty

All domains are resolved.

Configured

Empty

Only domains on the whitelist are resolved. All others are blocked.

Empty

Configured

Domains on the blacklist are blocked. All others are resolved.

Configured

Configured

Domains on the blacklist are blocked. Domains on the whitelist (but not on the blacklist) are resolved. All other domains are blocked.

Both lists support bulk operations.

Reference

Blacklist and whitelist