By Leonard Wills, NERC CIP Reliability Specialist
A strong data recovery strategy remains critical for business continuity in power plants because any downtime can compromise both operations and compliance. To build an effective strategy, entities must define and align the following: the recovery point objective (RPO), the recovery time objective (RTO), and the service level agreement (SLA).
The Recovery Point Objective (RPO) defines the maximum amount of data – measured in time – an organization can tolerate losing. For example, if a power plant establishes an RPO of one hour, it must ensure backups occur frequently enough to lose no more than one hour of operational data in the event of a failure. Reducing the RPO requires more frequent replication or continuous data protection, which increases costs but reduces potential data loss.
The Recovery Time Objective (RTO) sets the maximum acceptable downtime before systems return to normal operations. For example, a BES Cyber Asset might require an RTO of 10 minutes to maintain visibility into grid conditions, while a corporate email system might require several hours. Shorter RTOs generally demand greater investment in redundant systems, automation, and disaster recovery testing.
The Service Level Agreement (SLA) defines the service levels and related obligations the vendor must deliver to the power plant. Entities must ensure that the SLA aligns with their RPO and RTO. If the SLA does not meet these objectives, the overall recovery plan fails and exposes the entity to operational losses and compliance penalties.
Another key component of data recovery involves implementing a robust data backup strategy. The traditional 3-2-1 rule requires three copies of data, stored on two different media types, with at least one copy kept offsite. However, evolving cyber threats have led to the adoption of the more resilient 3-2-1-1-0 rule. This approach requires three total copies of data (one primary and two backups), two different forms of media, one copy kept offsite, one copy maintained in an immutable or air-gapped format to protect against ransomware or insider threats, and zero errors verified through automated backup validation and restoration testing.
Lastly, the recovery site strategy impacts how quickly operations resume. A hot site maintains fully operational systems with real-time replication and allows near-instant failover. A warm site contains hardware and connectivity, but systems require configuration or partial data loading during failover. This strategy balances cost and resiliency. A cold site represents the least expensive option, providing only physical space and power and requiring full system installation, which causes long recovery times.
