Immutable Backup

An immutable backup is a protected recovery copy that cannot be changed or deleted until its defined retention period has expired.

Protection may be applied through hardened repositories, object locks, backup appliances, cloud storage or offline media. This preserves a trusted recovery point even when production systems, administrator accounts or conventional backup copies have been compromised.

Traditional backups can often be edited or deleted by authorised accounts, while immutable backups stop protected copies being changed until the retention lock expires.

Immutability reduces the risk of ransomware, compromised credentials or human error removing every usable recovery point. It complements encryption, access controls, monitoring and separate backup copies within a broader data protection strategy.

Immutable backups can preserve clean recovery copies when ransomware encrypts production data or uses compromised administrative access to delete reachable backups.

They do not prevent the original attack, and an immutable copy may still contain infected or corrupted data. Steel City Consulting can align retention, backup frequency and recovery testing so suitable restore points remain available when an incident is discovered.

Backups should remain immutable for long enough to exceed likely threat detection times while still meeting recovery, regulatory, storage capacity and data retention requirements.

A short lock may expire before ransomware or corruption is discovered, whereas excessive retention can increase capacity and cost. We can model backup frequency, daily change rates and required recovery points to establish a practical retention period for each workload.

Yes, immutable backups still need regular recovery testing because protection from alteration does not guarantee the data is complete, usable or restorable.

Testing reveals missing dependencies, inaccessible credentials and unrealistic restoration times before an actual incident. Recovery exercises should cover applications, databases, network access and service order to confirm protected copies support recovery objectives rather than merely existing in storage.

Organisations should assess protected workloads, retention, administrator access, storage capacity, platform compatibility and acceptable recovery times before implementing immutable backup.

Monitoring, legal holds and recovery from a compromised management environment also affect the design. Steel City Consulting can assess these dependencies and configure appropriate controls, preserving trusted recovery copies without making legitimate lifecycle management or restoration unnecessarily difficult.