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Provider pair

Azure DNS + Cloudflare DNS: one DNS zone on both

Run the same zone on Azure DNS and Cloudflare at once. RedundantDNS writes every change to both, verifies them and probes their nameservers, and the NS set at your registrar lists both, so either one can answer.

How this pair behaves

  • Azure DNS: the apex NS is extended with the nameservers of every provider; Azure’s own nameservers always stay in the set.
  • Cloudflare: the apex NS is rewritten to list the nameservers of every provider, with Cloudflare’s Multi-provider DNS setting on (RedundantDNS turns it on when it attaches the zone).
  • Both Azure DNS and Cloudflare serve the full nameserver plan at the apex: RedundantDNS turns on Cloudflare’s Multi-provider DNS setting when it attaches the zone.
  • This needs a registrar where you can edit the NS set. A domain registered at Cloudflare Registrar stays on Cloudflare’s nameservers only; see the note below.
  • The zone accepts TTLs from 60 seconds to one day, the range Cloudflare supports.
  • Records per record set are capped at 20 and TXT at 4,096 characters per record set, because Azure is attached.
  • Features that only one provider has (for example Azure alias record sets) are outside the canonical zone. The zone's capabilities are the intersection of both providers.

Registered at Cloudflare Registrar?

Cloudflare Registrar only allows Cloudflare’s nameservers, so the apex of a domain registered there cannot be on Azure DNS too. Subdomains such as api. can, with no transfer, and the apex can once the registration moves to another registrar.

Read the Cloudflare Registrar guide

Set it up

  1. Connect Azure DNS with an app registration (service principal) with a client secret (permission guide).
  2. Connect Cloudflare DNS with an API token (permission guide).
  3. Create the zone in RedundantDNS, or adopt the one you already have on either provider.
  4. Attach both connections. RedundantDNS creates or adopts the zone on each and applies the records.
  5. Set the NS records at your registrar to the nameservers of both providers, as the dashboard lists them. The delegation check tells you when it is live.
One canonical zone synced to Azure DNS and Cloudflare DNS; the registrar's NS set lists both, and a resolver can ask any nameserver.

Permissions, per access level

Pick the level per connection. The guides have the exact policies and roles to copy.

Provider Create and manage zones Manage an existing zone
Azure DNS Built-in role DNS Zone Contributor on the resource group. DNS Zone Contributor scoped to the zone resource only (Azure supports per-zone role assignments).
Cloudflare DNS Custom API token with Zone · Zone Edit and Zone · DNS Edit on one account. Custom API token with Zone · Zone Read and Zone · DNS Edit on one specific zone.

Good to know about each provider

Azure DNS

  • Every zone attached to Azure takes Azure’s limits: at most 20 records per record set and 4,096 characters of TXT per record set.
  • Alias record sets that point at Azure resources are left alone.

Cloudflare DNS

  • RedundantDNS turns on Cloudflare’s Multi-provider DNS setting when it attaches a zone. With it on, Cloudflare honors the NS records at the apex and activates the zone even though the registrar also lists other providers’ nameservers.
  • Domains registered at Cloudflare Registrar can only use Cloudflare’s nameservers, so their apex cannot be multi-provider while they are registered there. Subdomains can. Cloudflare Registrar guide
  • Records are always written with the proxy off (DNS only), so every provider answers the same addresses. TTLs must be between 60 seconds and one day.

What the providers charge

With your own accounts you pay the providers directly and RedundantDNS charges only its plan. In managed mode these costs are passed through at cost plus 20%, line by line. Public list prices, collected on 2026-09-23; check the providers’ pages before relying on them.

Provider Per zone Queries
Azure DNS $0.50 per zone per month $0.40 per million
Cloudflare DNS free on the Free plan (DNS) free

Related pairs

Put your zone on Azure DNS and Cloudflare

Start with a 30-day trial: one zone on two providers you already have, no card. Plans from $9 a month after that.

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