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Provider pair

OCI DNS + Azure DNS: one DNS zone on both

Run the same zone on OCI 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

  • OCI 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.
  • 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 OCI DNS with an API signing key of an OCI user (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 OCI 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
OCI DNS Policy "manage dns" on one compartment: create zones there, write records and apex NS, delete on detach. Policy "use dns" with a condition on one zone OCID: read the zone and update its records, nothing else.
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

OCI DNS

  • Record sets are updated one at a time, idempotently. The SOA is never touched.

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
OCI DNS no per-zone charge $0.85 per million, with a monthly free allowance (check Oracle’s page for the exact allowance)
Azure DNS $0.50 per zone per month $0.40 per million

Put your zone on OCI 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.