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Provider pair

Google Cloud DNS + Azure DNS: one DNS zone on both

Run the same zone on Cloud DNS and Azure DNS 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

  • Cloud DNS: the apex NS is rewritten to list the nameservers of every provider.
  • Azure DNS: the apex NS is extended with the nameservers of every provider; Azure’s own nameservers always stay in the set.
  • Records per record set are capped at 20 and TXT at 4,096 characters per record set, because Azure is attached.
  • With the "manage an existing zone" level on Cloud DNS, the key can edit every zone in its project: use a dedicated project for isolation.
  • 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.

Set it up

  1. Connect Google Cloud DNS with the JSON key of a service account (permission guide).
  2. Connect Azure DNS with an app registration (service principal) with a client secret (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 Google Cloud DNS and Azure 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
Google Cloud DNS Predefined role DNS Administrator (roles/dns.admin) on the project. A custom role with the managedZones get/list, changes and resourceRecordSets permissions. It cannot create or delete zones.
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).

Good to know about each provider

Google Cloud DNS

  • Cloud DNS has no per-zone permissions: the "existing zone" level can edit every zone in the project. Keep a zone that must be isolated in a dedicated project.
  • Changes replace whole record sets atomically; large updates are split into changes of at most 1,000 additions and 1,000 deletions. Record sets with a routing policy are left alone.

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.

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
Google Cloud DNS $0.20 per zone per month (first 25), then $0.10 $0.40 per million (first billion), then $0.20
Azure DNS $0.50 per zone per month $0.40 per million

Put your zone on Cloud DNS and Azure DNS

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