Oracle Active Data Guard Licensing: The Definitive Guide for CIOs and IT Leaders

1. What Is Oracle Active Data Guard?

Oracle Active Data Guard (ADG) is a separately licensed Enterprise Edition option that transforms a passive disaster recovery standby database into an active, productive asset. While standard Data Guard — included free with Oracle Database Enterprise Edition — maintains a synchronised standby for failover, ADG goes further by allowing that standby to serve read-only queries, run backups, and provide real-time reporting while continuously applying redo from the primary database.

For licensing professionals, the distinction matters enormously. Data Guard itself costs nothing beyond your Enterprise Edition licence. The moment you open that standby for read-only queries — or enable any ADG feature such as real-time query, automatic block repair, Far Sync, or DML redirection — you enter Active Data Guard territory, and Oracle requires a separate, paid option licence on every environment involved. For a comprehensive overview of all Oracle Database editions and options, see our Oracle Database Licensing Guide.

Key Active Data Guard Features

Real-Time Query allows read-only workloads — reports, ad-hoc selects, analytics — to run on a synchronised standby database. This offloads the primary, provides read scalability, and continuously validates failover readiness.

Automatic Block Repair transparently fixes physical data block corruption on either the primary or standby by fetching the correct block from the other database.

Far Sync enables zero-data-loss protection over long distances by shipping redo to a lightweight Far Sync instance (with negligible performance overhead), which then forwards it to the actual standby.

Fast Incremental Backup offloads RMAN backups to the standby using Block Change Tracking, improving backup performance by up to 20× without impacting the primary.

DML Redirection (Oracle 19c+) allows certain write operations on the read-only standby by transparently forwarding them to the primary, enabling application flexibility while maintaining data consistency.

Rolling Upgrades allow the standby to apply patches and database upgrades, then switch roles with the primary, minimising downtime during maintenance windows.

2. Data Guard vs Active Data Guard: What Requires a Licence

The boundary between free Data Guard and paid Active Data Guard is the single most important licensing distinction for disaster recovery environments. Getting it wrong — in either direction — costs real money.

For detailed guidance on how Oracle handles standby and failover environments, including the passive DR exemption, see our Oracle Failover Licensing and Disaster Recovery Guide.

3. ADG Pricing: What It Actually Costs

Oracle Active Data Guard is priced as a standard Enterprise Edition option. The list prices, taken from the Oracle Technology Price List, are as follows:

These prices apply per environment. Since Oracle requires ADG to be licensed on both the primary and each standby server, the effective cost doubles for a typical single-primary, single-standby configuration.

Real-World Cost Example

Consider an organisation running Oracle Database EE on a 2-socket Intel server with 16 cores per socket (32 total cores). Using Oracle's 0.5 core factor for Intel x86 processors, this translates to 16 processor licences. For a detailed walkthrough of this calculation, see our Oracle Core Factor Table guide.

This is in addition to the Oracle Database EE licence cost ($47,500 per processor list price). The combined DB EE + ADG cost for this configuration would exceed $2M at list price — before any negotiation.

4. Named User Plus vs Processor: Choosing the Right Metric

Oracle offers two licensing models for ADG — Named User Plus (NUP) and Processor — and the choice must match how your Oracle Database Enterprise Edition is licensed. You cannot mix metrics: if the database is licensed by Processor, ADG must also be Processor-licensed. For a comprehensive comparison, see our guide on Named User Plus vs Processor licensing.

The Minimum NUP Trap

Oracle requires a minimum of 25 Named User Plus licences per processor for Enterprise Edition and all its options — including ADG. Even if only 5 DBAs access the standby for reporting, if the standby server has 4 processors (after core factor), you need at least 100 NUP licences (4 × 25). At $230 each, that's $23,000 — compared to $46,000 for 4 processor licences at list. NUP appears cheaper, but the minimum requirement narrows the gap significantly. See our detailed analysis of Oracle NUP minimum requirements.

Matching the Primary Database Metric

The ADG licence metric and quantity must match or exceed the primary database licence. If your primary DB is licensed for 100 NUP, ADG needs at least 100 NUP. If the primary has 8 processor licences, ADG needs at least 8 per environment. This matching principle prevents organisations from gaming the metric by choosing a cheaper model for the option than for the base product.

5. Licensing Rules: Primary, Standby, and Everything In Between

Oracle's ADG licensing rules are specific and strictly enforced during audits. Misinterpreting any of them can create significant compliance exposure. Here are the rules that matter most.

Rule 1: Enterprise Edition Only

Active Data Guard is exclusively an Enterprise Edition option. It cannot be used with Standard Edition 2 databases (which lack Data Guard entirely). For a comparison of editions, see our Oracle Database Licensing Guide.

Rule 2: Licence Both Primary and Standby

This is the rule that catches most organisations off-guard. Oracle requires the ADG option to be licensed on both the primary database server and every standby server in the Data Guard configuration. The rationale is that the primary actively participates in ADG features (sending redo, supporting block repair, handling DML redirection). If you have one primary and two active standbys, you need ADG licences on all three environments.

Rule 3: Matching Metric and Quantity

The licensing metric (NUP or Processor) must be identical to the primary database metric. The quantity must be at least equal — you cannot licence ADG for fewer users or processors than the database itself. If NUP licences the primary for 200 users, ADG needs 200 NUP per environment.

Rule 4: Per-Server Core Calculations

When licensing by Processor, calculate the requirement for each server independently based on its own hardware. If the primary runs on a 32-core server (16 processors after core factor) and the standby on a 16-core server (8 processors), licence 16 ADG processors for the primary and 8 for the standby. Each environment stands alone.

Rule 5: No Partial Licensing

You cannot license ADG on just the standby or just the primary. If ADG features are active anywhere in the Data Guard configuration, every participating database needs the option licence. Similarly, you cannot license ADG for only some standbys in a multi-standby configuration — every standby using ADG features must have it.

Rule 6: All Environments Include Non-Production

If you enable ADG features in development, test, or QA environments, those environments also need ADG licences. Oracle provides no free-use exception for ADG in non-production settings (unless covered under specific contract terms like a ULA).

6. The 10-Day Failover Rule and Passive DR Exceptions

Oracle provides a limited licensing exemption for purely passive disaster recovery standby databases. This is often called the "10-day rule" and it applies to the base database licence — but critically, it does not apply when Active Data Guard is in use.

How the 10-Day Rule Works

Oracle permits a single failover standby database to operate without a separate database licence for up to 10 separate days (24-hour periods) per year. This covers genuine disaster recovery activations and brief failover tests. Any usage beyond 10 days requires the standby to be fully licensed. Only one failover node qualifies for this exemption, and any activation — including maintenance, patching, or testing — counts against the limit.

Why the 10-Day Rule Doesn't Apply to ADG

The failover exemption is designed for passive standbys that remain in mount state during normal operations. When you use Active Data Guard, the standby is by definition active — open for read-only queries, running backups, applying redo in real-time. This continuous active usage means the standby must be fully licensed for both the Oracle Database EE and the ADG option from day one, regardless of the 10-day rule.

However, if you deploy a genuinely passive standby (no ADG features, database in mount state, activated only during emergencies), the 10-day rule can save you the cost of a full DB EE licence on that standby. The moment you add ADG capabilities, that savings disappears. For complete failover and DR licensing details, see our Oracle Disaster Recovery Licensing Guide.

7. Virtualization: The Hidden ADG Licensing Trap

Virtualization is where Active Data Guard licensing becomes genuinely dangerous — and where the largest compliance gaps typically appear. Oracle's virtualization rules apply to ADG exactly as they do to the base database licence, and they are far more restrictive than most organisations expect.

Soft Partitioning: The Full-Cluster Liability

Oracle classifies VMware vSphere, Microsoft Hyper-V, Docker containers, and most common hypervisors as soft partitioning. Under Oracle's policy, soft partitioning cannot be used to limit licensing scope. If your Oracle database runs on a VM with 4 vCPUs within a VMware cluster of 5 hosts (each with 16 cores), Oracle's position is that you must license all 80 cores across the entire cluster — not just the 4 vCPUs allocated to your VM.

For Active Data Guard, this liability applies to both the primary and standby environments. If both run on VMware clusters, you could face ADG licensing requirements across two full clusters — potentially hundreds of cores.

For a comprehensive treatment of this issue, see our Oracle Partitioning Policy guide and our Oracle Licensing in Virtualised Environments article.

Hard Partitioning: The Safe Path

Oracle recognises a limited set of technologies as hard partitioning — methods that physically constrain Oracle to specific CPU cores. These include Oracle VM (with CPU pinning), Oracle Linux KVM (with hard partitioning), IBM LPAR, and Solaris Zones. When properly configured, hard partitioning allows you to license only the cores allocated to Oracle, dramatically reducing the ADG licence requirement.

Practical Mitigation Strategies

Dedicated Oracle clusters. If you must run on VMware, create isolated VMware clusters exclusively for Oracle workloads. Pin Oracle VMs to these clusters with strict affinity rules and document that Oracle VMs cannot migrate to other clusters. While not a bulletproof defence against Oracle's full-cluster policy, it significantly reduces the scope of any licensing claim.

Physical servers for standby. In some cases, running the standby database on a dedicated physical server (rather than a shared VM cluster) is cheaper once you factor in ADG licensing costs across a virtual environment. The hardware cost may be lower than the licensing premium.

Oracle VM or KVM. If hard partitioning is an option, migrating ADG workloads to an Oracle-approved hypervisor can cut licensing costs by 70-90% compared to licensing an entire VMware cluster.

8. Cloud Licensing: BYOL, OCI, and Authorised Cloud Environments

Oracle's ADG licensing rules apply equally in cloud environments. Whether you deploy on Oracle Cloud Infrastructure (OCI), AWS, or Azure under a Bring Your Own License (BYOL) model, Active Data Guard must be properly licensed. For a detailed treatment of cloud-specific rules, see our guide on Oracle Database Licensing in Cloud Environments.

Oracle Cloud Infrastructure (OCI)

OCI offers the most favourable licensing terms. Under BYOL, 1 OCPU = 1 Oracle processor licence. If you activate 8 OCPUs for a database, you need 8 ADG processor licences per environment. Alternatively, OCI offers a license-included subscription where ADG can be enabled as a cloud service add-on for an additional hourly charge — simplifying licence management but increasing operational costs.

AWS and Azure (Authorised Cloud Environments)

On AWS and Azure, Oracle's Authorised Cloud Environment policy applies. The standard conversion is 2 vCPUs = 1 processor licence (assuming hyper-threading is enabled). For ADG BYOL on a 16-vCPU EC2 instance, you'd need 8 processor licences for the database and 8 additional ADG processor licences — per environment. The Oracle Core Factor Table does not apply in cloud environments; the simplified vCPU conversion rule applies instead.

Cloud DR Architecture Implications

Many organisations use cross-region Data Guard replication in the cloud for disaster recovery. If the DR region's standby uses ADG features (even just read-only reporting), it must be fully licensed. Cloud deployment is not a licensing loophole — Oracle's BYOL compliance checks will verify that you have sufficient ADG licences allocated to cover all cloud instances where ADG is active.

9. The 7 Most Expensive ADG Licensing Mistakes

These are the mistakes we encounter most frequently in ADG licensing engagements. Each one can result in six- or seven-figure compliance exposure.

• Assuming Data Guard = Active Data Guard. Opening a standby database for read-only reporting requires the ADG option licence. Data Guard is free; the "Active" capability is not. This is the single most common ADG compliance violation, and Oracle's audit scripts specifically detect standby database open modes.
• Not licensing the standby environment. Oracle requires ADG licences on both the primary and the standby. Licensing only the primary (or undercounting the standby's cores) leaves a compliance gap that Oracle will identify in any audit. Calculate licence requirements for each server independently.
• Mixing licence metrics. Using NUP for the primary database and Processor for ADG (or vice versa) violates Oracle's matching requirement. All database options must follow the same metric as the base product. This creates a messy compliance situation that is expensive to unwind.
• Ignoring NUP minimums. Even if only 8 DBAs access the standby, the 25-NUP-per-processor minimum applies. On a 4-processor server, you need at least 100 NUP licences — regardless of actual user count. Failing to meet minimums is a compliance violation.
• VMware full-cluster licensing failures. Running ADG on a VM in a shared VMware cluster without understanding Oracle's soft partitioning policy can result in licensing demands for every core in the cluster. This single mistake regularly generates $1M+ audit findings.
• Overlooking implicit ADG feature usage. Enabling Automatic Block Repair, DML Redirection, or Fast Incremental Backup on a standby may not be as obvious as opening the database read-only — but these are all ADG features that require licensing. Always cross-check which features are active on your standbys.
• Claiming the 10-day rule while using ADG. The passive failover exemption does not apply when Active Data Guard is in use. If the standby is continuously synchronised and open for queries, it must be fully licensed from day one — there is no 10-day grace period for active standbys. See our Oracle Audit Strategic Guide for more on audit defence.

10. Best Practices for ADG Licence Optimisation

Active Data Guard is expensive, but there are legitimate ways to optimise costs while staying compliant. These recommendations are drawn from hundreds of ADG licensing engagements across our client base.

Practice 1: Assess Before You Enable

Before activating any ADG feature, perform a thorough licensing assessment. Calculate the total cost across all environments — primary, standby, and any non-production systems. Compare this against the business value of having an active standby. In some cases, the cost of ADG licensing exceeds the value of the reporting capability, and a simple Data Guard configuration (with a separate reporting database refreshed periodically) is more cost-effective.

Practice 2: Right-Size Your Hardware

Since ADG is licensed per processor, the standby server's core count directly drives cost. If the standby only serves read-only reporting, it may not need the same hardware specification as the primary. A smaller standby server (fewer cores) means fewer ADG processor licences. Just ensure performance is adequate for your reporting workload.

Practice 3: Consolidate Standby Workloads

If you have multiple primary databases, you might not need ADG on every standby. Identify which databases genuinely benefit from active standby capabilities (read offload, real-time reporting) and which can use standard Data Guard. Licensing ADG on one strategic standby rather than five can save hundreds of thousands of dollars. For contract negotiation strategies, see our guide on managing Oracle contracts.

Practice 4: Use Hard Partitioning Where Possible

In virtualised environments, migrating ADG workloads to Oracle-approved hard partitioning technologies (Oracle VM, Oracle Linux KVM) can reduce licensing scope from full cluster to pinned cores — often a 60-80% cost reduction. The migration cost is almost always less than the licensing savings.

Practice 5: Document Everything

Maintain clear records of every environment where ADG is (and isn't) deployed. Document hardware specifications, core counts, core factors, standby database open modes, and the business purpose of each standby. Distinguish clearly between passive Data Guard standbys and active ADG standbys. This documentation is your primary defence in an audit.

Practice 6: Run Internal Audits Regularly

Oracle's LMS scripts can detect ADG feature usage via DBA_FEATURE_USAGE_STATISTICS. Run these scripts internally — quarterly at minimum — to catch accidental ADG usage (e.g., a DBA opening a standby for read-only access without realising the licensing implications). Proactive identification allows you to remediate before Oracle's audit team finds it.

Practice 7: Negotiate ADG Into Broader Deals

Never purchase ADG as a standalone add-on after the initial database purchase. The best discounts come when ADG is included in the original database contract, a ULA, or a broader Oracle negotiation. Leverage competitive pressure (third-party replication tools, cloud-native DR) to drive down ADG pricing.

11. FAQ: Oracle Active Data Guard Licensing

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