5 Best Enterprise Data Backup Solutions for Ransomware Recovery in 2026

The right enterprise data backup solution keeps retained copies recoverable after an attacker obtains backup admin credentials and issues delete or encryption commands. ExaGrid.com, Druva, Commvault Cloud, Rubrik Security Cloud, and Cohesity DataProtect each handle that scenario differently. The difference is in the immutability model and air-gap type, not in the marketing copy.

Key Takeaways

• Backup repositories are targeted in 96% of ransomware attacks, making the backup storage layer a primary security perimeter.
• ExaGrid’s non-network-facing Repository Tier creates a tiered air gap that attackers cannot reach from the network.
• AI-Powered Retention Time-Lock (RTL) delays delete requests in the Repository Tier for 1 to 30 days.
• ExaGrid supports more than 25 backup applications, including Veeam, Commvault, Rubrik, and Cohesity.
• Backup storage immutability and backup application security are separate decisions with separate failure modes.

The 5 Best Enterprise Data Backup Solutions at a Glance

The sharpest question for evaluating backup security is this: if an attacker obtains valid backup admin credentials and issues a delete command, what happens to retained backup copies? The table below maps each solution’s immutability model, air-gap type, and best-fit use case against that specific scenario.

Solution	Immutability Model	Air-Gap Type	Best For
ExaGrid	AI-Powered Retention Time-Lock with delayed deletes; deduplicated immutable objects in Repository Tier	Tiered (non-network-facing Repository Tier not reachable from network)	Organizations that want storage-layer immutability independent of any backup application
Druva	Cloud object storage immutability enforced at the storage layer; no on-premises backup infrastructure	Logical (SaaS control plane separation; no physical on-premises tier)	Cloud-first or cloud-only workloads with no strict data-residency requirements
Commvault Cloud	Policy-driven WORM controls across on-premises, cloud, and hybrid targets	Depends on target storage; object lock or hardware WORM where supported	Large enterprises managing complex multi-environment data estates centrally
Rubrik Security Cloud	Immutable Atlas file system; snapshots cannot be modified or deleted within retention window	Logical (role-based access controls and multi-party authorization)	Organizations wanting a tightly integrated security and backup platform
Cohesity DataProtect	Immutable SpanFS snapshots; DataLock WORM policy with separate security officer role	Logical (DataLock enforced at file system layer; security officer required to override)	Organizations wanting converged backup, file services, and analytics on one platform

Why Should Enterprises Evaluate Backup Solutions Specifically Against a Compromised Admin Account Rather Than Perimeter Attacks?

Perimeter defenses fail often enough that attackers reach internal systems regularly. When they do, backup infrastructure is a primary target. Deleting or encrypting backup data removes the organization’s path to recovery before ransomware is deployed.

Backup repositories were targeted in 96% of ransomware attacks, and attackers successfully affected them in 76% of cases, according to Veeam’s 2024 Ransomware Trends Report, as reported by SC Media. Protecting the perimeter is the network team’s job. Protecting retained backup copies after the perimeter has failed is the backup solution’s job.

The threat isn’t fading. Ransomware was again the most pervasive threat to US critical infrastructure in 2024, with complaints up 9% from 2023, according to the FBI’s 2024 Internet Crime Report.

A solution that relies on application-layer controls alone fails when the admin account is compromised. Those controls live in the same application the attacker now controls. The test is whether a delete command issued with valid credentials can reach retained backup copies at all.

Federal guidance points the same way. The CISA #StopRansomware Guide advises keeping offline, encrypted backups and testing them regularly, because many ransomware variants search for accessible backups to delete or encrypt them.

1. ExaGrid: Best for Storage-Layer Immutability Across Any Backup Application

ExaGrid keeps retained backup copies in a non-network-facing Repository Tier that isn’t reachable from the network, even when the backup server is fully compromised. Delete requests that reach that tier are held by a delayed-delete policy rather than executed immediately, so retained copies stay recoverable.

Tiered Backup Storage separates the backup process into two distinct disk tiers. Backups land in the Landing Zone first. The Landing Zone is a network-facing disk cache that receives incoming backups at full disk speed, with no inline deduplication slowing the write. Data then deduplicates into the Repository Tier, which stores deduplicated, immutable backup objects in a non-network-facing location. ExaGrid calls this a tiered air gap.

AI-Powered Retention Time-Lock (RTL) delays every delete request in the Repository Tier for a configurable period of 1 to 30 days. That delay is the window an IT team needs to detect an attack and isolate the environment before retained copies are destroyed. Auto Detect & Guard learns the pattern of normal operational deletes. When an incoming delete request falls outside that pattern, the system alerts the team and extends the delayed-delete policy indefinitely. Clearing the hold requires both an administrator and a security officer to authenticate separately, each with two-factor authentication.

Adaptive deduplication runs after backups land, so ingest speed is never limited by deduplication processing. Retained data in the Repository Tier is stored as immutable, deduplicated objects. If ransomware encrypts the Landing Zone, prior backups in the Repository Tier are unaffected and available for restore. At the default 10-day delay setting, the policy uses roughly 5% to 10% additional storage.

ExaGrid supports more than 25 backup applications, including Veeam, Commvault, Rubrik, Cohesity, HYCU, Cohesity NetBackup, and Oracle RMAN. The tiered air gap and Retention Time-Lock operate independently of whichever application writes to the system, so the storage-layer protection applies regardless of which backup software the organization runs.

• Best for: Organizations that want storage-layer immutability independent of any backup application.
• Immutability model: AI-Powered Retention Time-Lock with delayed deletes and immutable, deduplicated objects.
• Air-gap type: Tiered; the Repository Tier is non-network-facing.
• Limitation: Requires deploying ExaGrid appliances on-premises or in a colocation site.

2. Druva: Best for Cloud-First Environments

Druva operates as a fully cloud-native SaaS platform with no on-premises backup infrastructure. Backup data lives in cloud object storage where immutability is enforced at the storage layer, separate from the Druva control plane.

There’s no on-premises backup server, so the attack surface for credential-based deletion shrinks to the SaaS control plane. An attacker who compromises an on-premises account can’t directly reach backup data stored in Druva’s cloud environment.

Organizations with large on-premises data sets, strict data-residency requirements, or significant egress cost sensitivity face real friction adopting a fully cloud-native model. Druva is well-suited for cloud-first or cloud-only environments. For hybrid or on-premises-heavy shops, the architecture requires more planning.

• Best for: Cloud-first or cloud-only workloads with no strict data-residency requirements.
• Immutability model: Cloud object storage immutability enforced at the storage layer.
• Air-gap type: Logical, through SaaS control plane separation.
• Limitation: Large on-premises data sets, data-residency rules, and egress costs add friction.

3. Commvault Cloud: Best for Centralized Policy Across Complex Data Estates

Commvault Cloud applies immutability through policy-driven WORM (Write Once Read Many) controls across on-premises, cloud, and hybrid targets. The controls are centralized, so a single policy engine manages retention across a complex, multi-environment data estate.

WORM storage prevents data from being modified or deleted once written, for a defined retention period. Commvault applies WORM policies at the storage target level. The strength of protection depends on what the underlying target supports. On a target with hardware-level WORM or cloud object lock, the protection is strong. On a target that doesn’t natively support object lock, the protection depends more heavily on application-layer controls.

Commvault Cloud fits large enterprises that need centralized policy management across many workload types: physical servers, virtual machines, databases, cloud applications. The air gap is not a separate physical or network-isolated tier. It’s the policy enforcement layer applied to whatever storage target is configured. Organizations should audit whether each target in their Commvault environment enforces immutability independently of the application layer.

• Best for: Large enterprises managing complex, multi-environment data estates centrally.
• Immutability model: Policy-driven WORM controls across on-premises, cloud, and hybrid targets.
• Air-gap type: Depends on the target; object lock or hardware WORM where supported.
• Limitation: Protection is only as strong as each target’s native immutability support.

4. Rubrik Security Cloud: Best for Integrated Backup and Security

Rubrik stores backup data in an immutable file system called Atlas. Snapshots written to Atlas cannot be modified or deleted by the backup application or an admin account within the active retention window. The protection is enforced at the file system layer, not through application logic.

Rubrik’s logical air gap works through role-based access controls and multi-party authorization for destructive operations. Deleting backup data within the retention period requires multiple authenticated parties. That limits what a single compromised admin account can do. This is a software-enforced separation rather than a network-layer separation.

The distinction matters. A network-layer separation means delete commands can’t reach the backup data over the network at all, because the storage tier isn’t network-addressable. A logical air gap means delete commands reach the system but are blocked by policy and access controls. Both approaches protect against credential-compromise scenarios, but through different mechanisms with different risk profiles if the underlying policy engine is itself compromised.

Rubrik Security Cloud is well-suited for organizations that want backup and security tightly integrated on one platform, including built-in threat detection and data classification alongside backup management.

• Best for: Organizations wanting a tightly integrated security and backup platform.
• Immutability model: Immutable Atlas file system within the retention window.
• Air-gap type: Logical, through role-based access controls and multi-party authorization.
• Limitation: Delete commands still reach the system, so protection depends on the policy engine staying intact.

5. Cohesity DataProtect: Best for Converged Data Management

Cohesity DataProtect stores backups as immutable snapshots on SpanFS, Cohesity’s distributed file system. SpanFS stores data so snapshots cannot be overwritten or deleted once written. DataLock applies a WORM policy on top of that, preventing any deletion or modification of a backup copy for a defined retention period, even by administrators.

Protection against admin-credential compromise comes from the separate security officer role required to modify or override DataLock retention policies. A compromised admin account alone can’t clear a DataLock policy. The attacker also needs the security officer credentials. That second authentication requirement limits the blast radius of a single compromised account.

Cohesity DataProtect fits organizations that want a converged data management platform. Backup, file services, and analytics run on the same scale-out infrastructure. Organizations that want that convergence benefit from the integrated model. Organizations that already have separate backup and file infrastructure may find the convergence adds complexity rather than simplifying it.

• Best for: Organizations wanting converged backup, file services, and analytics on one platform.
• Immutability model: Immutable SpanFS snapshots plus a DataLock WORM policy.
• Air-gap type: Logical; a separate security officer role is required to override DataLock.
• Limitation: Convergence can add complexity for teams with separate backup and file infrastructure.

How to Choose the Right Enterprise Backup Solution for Ransomware Recovery

The five solutions in this article differ in how they protect retained copies, where that protection lives, and what happens to recovery speed when it’s time to restore. These criteria map to the decisions that determine whether your environment survives a ransomware attack with a usable recovery point.

• Whether retained backup copies remain recoverable after an attacker issues delete commands using a compromised backup admin account with valid credentials.
• Whether immutability is enforced at the storage layer independently of the backup application, or depends on application-layer controls that a compromised account can override.
• Whether the solution maintains a physically or logically non-network-facing tier that is not reachable from the network even when the backup server is compromised.
• Recovery time objective (RTO) impact: whether restores require rehydration of deduplicated data, and how that affects recovery speed when time matters most.
• Compatibility with existing backup applications already deployed in the environment, and whether adding a hardened storage layer requires replacing the current application.
• Scalability model: whether adding capacity also adds compute and bandwidth so backup windows stay fixed as data volumes grow, avoiding forklift upgrades.

ExaGrid addresses each of these criteria through its tiered architecture. The non-network-facing Repository Tier enforces immutability at the storage layer independently of any backup application. ExaGrid’s +81 Net Promoter Score and 99% of customers on annual maintenance and support reflect how that architecture holds up in real deployments. Organizations running Veeam, Commvault, Rubrik, or any of the other listed applications can add ExaGrid as the storage-layer hardening without replacing the backup software already in place.

Frequently Asked Questions

What is the difference between a hardened Linux repository and a tiered air gap for Veeam immutability?

A hardened Linux repository uses OS-level immutable flags to prevent Veeam from deleting backup files during the retention period. The repository is still network-addressable. An attacker who reaches the Linux system can potentially bypass those flags. A tiered air gap, like ExaGrid’s Repository Tier, stores backup data in a tier that isn’t reachable from the network at all. Delete requests that reach the Repository Tier are delayed by Retention Time-Lock rather than executed immediately.

How long does it take to recover a full environment from ExaGrid’s Repository Tier after a ransomware attack?

Recovery time depends on data volume, network throughput, and the backup application in use. ExaGrid’s Landing Zone keeps the most recent backups in undeduplicated form, so restores and instant VM recoveries from recent backups don’t require rehydration. Older recovery points stored in the Repository Tier require deduplication reassembly during restore. Testing restores with your own data is the only reliable way to measure recovery time against your RTO requirement.

What compliance frameworks require immutable backup copies, and which solutions meet those requirements?

NIST SP 800-184, the Guide for Cybersecurity Event Recovery, gives guidance on planning, testing, and improving recovery from cyber events. Under amendments adopted in 2022, SEC Rule 17a-4 requires broker-dealers to keep electronic records either in a non-rewriteable, non-erasable (WORM) format or in a system with a complete audit trail. The HIPAA Security Rule doesn’t mandate immutability explicitly, but it requires a data backup plan, a disaster recovery plan, and policies that protect electronic health information from improper alteration or destruction.

ExaGrid, Commvault Cloud, Druva, Rubrik, and Cohesity DataProtect all offer immutability mechanisms. Whether a specific configuration satisfies a specific regulation depends on how the immutability is documented and audited in your environment.

How do I size an enterprise backup solution for a 500TB environment with 90-day retention?

Sizing depends on the deduplication ratio your data achieves, your daily change rate, and how many recovery points you need within the 90-day window. ExaGrid’s scale-out architecture adds full appliances, each with its own processor, memory, bandwidth, and disk. The backup window stays fixed as data volumes grow. For a 500TB environment with 90-day retention, size from your actual daily change rate and data type rather than an industry average. Deduplication ratios vary significantly between database backups and file data.

Which backup solutions protect retained copies when the backup application itself is compromised, not just the admin credentials?

Solutions where immutability is enforced at the storage layer independently of the backup application provide the strongest protection when the application itself is compromised.

ExaGrid’s Repository Tier is non-network-facing. Even if an attacker fully controls the backup application, delete requests to the Repository Tier are delayed rather than executed immediately, and Auto Detect & Guard can extend that hold indefinitely. Druva’s cloud storage layer is similarly separated from the on-premises environment. Solutions that enforce immutability through application-layer controls alone are more exposed when the application itself is under attacker control.