API
Cloudflare
The foundation_dns boolean in Cloudflare's DNS settings endpoints (/zones/{zone_id}/dns_settings and /accounts/{account_id}/dns_settings) is deprecated; code must select Advanced Nameservers via nameservers.type: "cloudflare.advanced" instead
departs 23 Nov 2026
Quick answers
- Is it true that Cloudflare deprecates the foundation_dns boolean in the DNS settings API — end-of-life 23 November 2026, switch to nameservers.type cloudflare.advanced?
- Yes. Cloudflare has officially announced it, effective 23 Nov 2026. This affects any automation that reads or sets Advanced Nameservers (Cloudflare's Foundation DNS feature) through the API using the foundation_dns boolean.
- When does it take effect?
- 23 Nov 2026. Verified against the vendor's own announcement.
- What should I use instead?
- Update any code that reads or writes the foundation_dns boolean on /zones/{zone_id}/dns_settings or /accounts/{account_id}/dns_settings to use nameservers.type: "cloudflare.advanced" instead, before 23 November 2026.
What this means for you
This affects any automation that reads or sets Advanced Nameservers (Cloudflare's Foundation DNS feature) through the API using the foundation_dns boolean. On Cloudflare's deprecations page, that boolean is listed as deprecated on 27 July 2026 with an end-of-life date of 23 November 2026 in the DNS settings endpoints for both zone settings (/zones/{zone_id}/dns_settings) and account defaults (/accounts/{account_id}/dns_settings). The replacement is a different field on the same endpoints: nameservers.type set to "cloudflare.advanced". Cloudflare also warns of a transition window — beginning 26 October 2026, the DNS settings API gradually starts representing Advanced Nameservers with nameservers.type: "cloudflare.advanced", a rollout it expects to take about seven days per account. The practical risk is unattended: infrastructure-as-code and provisioning scripts that toggle foundation_dns, or that assert on it when reading settings, will drift or break as the representation changes and then as the field reaches end-of-life. Interactive dashboard users are unaffected.
Where to go
Update any code that reads or writes the foundation_dns boolean on /zones/{zone_id}/dns_settings or /accounts/{account_id}/dns_settings to use nameservers.type: "cloudflare.advanced" instead, before 23 November 2026. Because Cloudflare begins gradually re-representing Advanced Nameservers with the new field on 26 October 2026 (a rollout of roughly seven days), fix code that asserts on the old boolean before that window rather than at the end-of-life date — otherwise a config-drift check or a Terraform plan can start reporting spurious changes mid-rollout. Update generated clients, vendored wrappers, and any Terraform or CI steps that touch DNS settings, and re-test that reads and writes behave against the new field.
- Set nameservers.type: "cloudflare.advanced" on the DNS settings endpoints to configure Advanced Nameservers — Cloudflare's named replacement for the foundation_dns boolean
- The Cloudflare dashboard, which is unaffected by this API field deprecation
Cloudflare has scheduled the removal of a field in its DNS settings API. On the API deprecations page, the foundation_dns boolean is listed as deprecated on 27 July 2026 with an end-of-life date of 23 November 2026. It appears in the DNS settings endpoints for both zone settings (/zones/{zone_id}/dns_settings) and account defaults (/accounts/{account_id}/dns_settings).
The boolean is how the API currently indicates Cloudflare’s Advanced Nameservers (part of the Foundation DNS product). Its replacement is not a new endpoint but a different field on the same ones: set nameservers.type to "cloudflare.advanced". So this is a small, contained change — but one that lives inside infrastructure-as-code and provisioning scripts, which is exactly where a quiet field rename tends to bite.
There is also a transition window worth marking on the calendar before the end-of-life date. Cloudflare says that beginning 26 October 2026, the DNS settings API will gradually start representing Advanced Nameservers with nameservers.type: "cloudflare.advanced", a rollout it expects to take about seven days to reach an account. That matters for anything that reads settings and compares them: a drift check or a Terraform plan that asserts on the old foundation_dns value can start reporting spurious differences mid-rollout, well before November.
The fix is to move both reads and writes to nameservers.type: "cloudflare.advanced", update any generated clients or vendored wrappers, and adjust the Terraform or CI steps that touch DNS settings. Aim to have it done before the 26 October 2026 rollout window rather than waiting for the 23 November 2026 end-of-life, so a config-drift alarm does not fire on a change that is really Cloudflare’s own representation catching up.
This is one of several DNS-related API changes Cloudflare lists on the same deprecations page, alongside the REST DNS Analytics API retirement on 1 December 2026. If you provision Cloudflare DNS through the API, it is worth reading the page in full.
Entry changelog
- — last reviewed.
- — Entry created from Cloudflare's official API deprecations page (developers.cloudflare.com/fundamentals/api/reference/deprecations). The deprecation date (27 July 2026), the 23 November 2026 end-of-life date, the affected endpoints (/zones/{zone_id}/dns_settings and /accounts/{account_id}/dns_settings), the nameservers.type: "cloudflare.advanced" replacement, and the 26 October 2026 gradual-representation rollout are all quoted from that page. Added a detect: fingerprint (text:foundation_dns) so the lastcall CLI flags code still using the deprecated boolean.
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