CP-2(6): Alternate Processing and Storage Sites

CP-2(6) requires you to pre-plan and document how you will transfer designated mission and business functions to alternate processing and/or storage sites with minimal or no loss of continuity, and how you will sustain operations until the primary site is restored. Operationalize it by defining failover criteria, validating alternate site capability, and running evidence-backed tests. ¹

Key takeaways:

• You need a documented, executable transfer plan for specific functions, not a generic “DR statement.” ¹
• Auditors look for proof the alternate sites can actually run your workloads and protect your data, with repeatable tests and results.
• Evidence is the control: diagrams, runbooks, configs, test logs, and restoration records matter as much as architecture.

The cp-2(6): alternate processing and storage sites requirement sits in the Contingency Planning family and is assessed as part of how you maintain operational continuity when a primary processing location or storage location fails. The requirement is narrow but demanding: you must plan for transfer of defined mission and business functions to alternate processing and/or storage sites, with minimal or no loss of continuity, and then sustain that continuity through restoration back to the primary site. ¹

For a Compliance Officer, CCO, or GRC lead, the fastest path is to translate CP-2(6) into three operator-ready deliverables: (1) scope clarity (which functions, which systems, which dependencies), (2) an executable transfer and sustainment runbook (who does what, when, and with what tooling), and (3) evidence that the alternate site(s) can carry the load and preserve security and integrity of data during transfer and operations. This page is written to help you assign ownership, produce assessment-ready artifacts, and avoid the common trap of “we have backups” being mistaken for “we can process and store at an alternate site.”

Regulatory text

NIST SP 800-53 Rev. 5 CP-2(6) (excerpt): “Plan for the transfer of [organization-defined] mission and business functions to alternate processing and/or storage sites with minimal or no loss of operational continuity and sustain that continuity through system restoration to primary processing and/or storage sites.” ¹

What the operator must do with this text

• Plan the transfer: Document how you move targeted functions from primary to alternate processing and/or storage sites.
• Minimize continuity loss: Set transfer triggers and technical patterns (failover, warm standby, active-active, restore-from-backup) aligned to your continuity expectations.
• Sustain operations: Show you can operate from the alternate site for a meaningful period, not just flip traffic briefly.
• Restore back to primary: Include “return-to-primary” steps, data reconciliation, and validation criteria. ¹

Plain-English interpretation

CP-2(6) means you need a real, practiced plan to keep the business running when your primary compute and/or storage is unavailable. “Alternate site” can be a second data center, a second cloud region, a separate cloud account/tenant, or a third-party managed environment. The control is satisfied when you can demonstrate, with evidence, that:

1. you identified the functions that must continue,
2. you can move their processing and data storage to an alternate site quickly enough for your needs,
3. you can run there safely and reliably until primary is back, and
4. you can restore service back to primary without breaking integrity or losing track of changes. ¹

Who it applies to

Entities

• Federal information systems.
• Contractor systems handling federal data. ¹

Operational context (where you’ll feel CP-2(6) most)

• Systems with operational uptime requirements (customer-facing apps, revenue systems, safety or mission systems).
• Systems with regulated data handling where loss of availability becomes a security event or contractual breach.
• Hybrid architectures where “alternate processing” and “alternate storage” may be split across different platforms or third parties.

What you actually need to do (step-by-step)

1) Assign ownership and define the “organization-defined” scope

CP-2(6) contains an organization-defined parameter (the specific mission/business functions in scope). ¹

Create a short scoping memo that lists:

• In-scope functions (plain business language).
• Mapped systems/components (apps, databases, queues, identity dependencies).
• Authoritative owners: a business owner and a technical owner for each function.
• Continuity objectives you will use internally (for example, internal RTO/RPO targets). Keep them consistent across BC/DR documents even if you do not publish the numbers externally.

Practical tip: auditors will accept your defined scope if it is defensible and tied to mission/business impact, but they will challenge “everything is critical” when the plan is vague.

2) Identify alternate processing and alternate storage sites, and document separation

Document, in architecture terms:

• Primary processing site and primary storage site.
• Alternate processing site and/or alternate storage site.
• Independence assumptions: what failure modes the alternate site is meant to survive (region outage, data center outage, account compromise, network path outage).

This is where teams confuse backups with alternate storage. Backups help restoration; CP-2(6) expects planned transfer to an alternate site for continuity, then sustainment through restoration. ¹

3) Build the transfer runbook (primary → alternate)

Write an operator-grade runbook that includes:

• Trigger criteria (who declares a failover, what signals count).
• Pre-checks (data replication healthy, last successful snapshot, IAM readiness).
• Execution steps (DNS/traffic management changes, promotion of replicas, application config flips, secret rotation if needed).
• Decision points (when to stop, roll back, or escalate).
• Communications plan (internal incident channel, third-party notifications if dependencies exist).

Keep it actionable: a runbook that requires tribal knowledge fails in an exam because it cannot be executed reliably.

4) Prove sustainment capability (operating from alternate)

Sustainment is the part most programs under-document. Add:

• Capacity and dependency checklist: critical batch jobs, integrations, SSO, email/SMS, payment rails, logging/SIEM, monitoring, vulnerability scanning coverage.
• Security equivalence: confirm the alternate site enforces required controls (network segmentation, encryption, key management, access logging).
• Operational procedures: patching cadence, access approvals, break-glass process, incident response handoffs while in alternate mode.

Expectation to set: “We can run here, securely, until the primary is restored.” ¹

5) Build the restoration runbook (alternate → primary)

Restoring to primary is not “turn it back on.” Your restoration plan should include:

• Data reconciliation: how writes during alternate operations are captured and re-synced.
• Validation gates: application health, data integrity checks, user access validation, monitoring green status.
• Return criteria: who approves return-to-primary and how you record that decision.
• Post-return actions: incident retrospective, evidence packaging, and backlog items.

6) Test, record, and fix gaps on a schedule you can defend

CP-2(6) is plan-focused, but assessors expect operational proof. Establish a repeatable test approach:

• Tabletop for decision logic and roles (good for new services).
• Functional tests for specific components (database promotion, storage mount).
• Failover exercises for end-to-end continuity, where feasible.

Record outcomes, issues found, and remediation tickets. Tie each gap to a due date and owner.

7) Map CP-2(6) to control operations and recurring evidence (assessment readiness)

Make CP-2(6) audit-ready by mapping:

• Control owner(s)
• Implementation procedure
• Evidence produced per cycle (runbooks, test logs, approvals, change records)

Daydream (or a similar GRC workflow) helps here by turning CP-2(6) into a control with assigned ownership, tasks, and a standing evidence request list so you do not rebuild the story each audit.

Required evidence and artifacts to retain

Maintain a “CP-2(6) evidence packet” with:

• Scope definition of mission/business functions covered (the “organization-defined” list). ¹
• Architecture diagrams showing primary and alternate processing/storage sites and data flows.
• Runbooks: failover/transfer, sustainment operations, restoration/return-to-primary.
• Configuration evidence: replication settings, infrastructure-as-code references, traffic management config, backup/restore configurations where relevant.
• Test evidence: exercise plans, timestamps, participants, results, screenshots/log exports, after-action reports.
• Issue remediation trail: tickets, risk acceptances (if any), approvals, and closure evidence.
• Third-party contracts/SLA extracts when the alternate site is operated by a third party and continuity depends on their commitments.

Common exam/audit questions and hangups

Use these as your pre-audit checklist:

1. “Which mission and business functions are in scope, and who approved that list?”
   Hangup: scope is implied but not documented. CP-2(6) explicitly expects an organization-defined list. ¹

2. “Show me you can transfer processing and/or storage to the alternate site.”
   Hangup: diagrams exist, but no operator steps or evidence of execution.

3. “Can you sustain operations from the alternate site?”
   Hangup: failover works, but monitoring, access workflows, or third-party dependencies fail in alternate mode.

4. “Show restoration back to primary.”
   Hangup: teams test failover but never test failback. Data reconciliation is often missing.

5. “Where is the evidence from the last exercise?”
   Hangup: tests occurred, but logs and approvals were not retained in a centralized evidence location.

Frequent implementation mistakes and how to avoid them

• Mistake: Treating backups as alternate storage.
  Avoidance: explicitly document whether the alternate storage site supports continued operations, not only restoration.

• Mistake: Alternate site exists but is not security-equivalent.
  Avoidance: require baseline security controls at alternate sites (IAM, logging, encryption) and keep a short “security parity checklist” in the evidence packet.

• Mistake: Runbooks are aspirational.
  Avoidance: write runbooks as if a new on-call engineer must execute them at 2 a.m., then test them and update immediately.

• Mistake: No clear transfer authority.
  Avoidance: define who can declare a failover, who can approve return-to-primary, and how decisions are recorded.

• Mistake: Evidence sprawl.
  Avoidance: store CP-2(6) artifacts in one evidence location with version control. Daydream can track owners and recurring evidence so each audit cycle is a refresh, not a scramble.

Enforcement context and risk implications

No public enforcement cases were provided in the source catalog for this requirement, so you should treat enforcement expectations as assessment-driven rather than case-law-driven. The practical risk is operational: an unplanned site failure becomes a prolonged outage, data inconsistency, or a security incident caused by rushed access changes and ad hoc recovery steps. CP-2(6) reduces that risk by forcing pre-approval and repeatable execution. ¹

Practical 30/60/90-day execution plan

Days 0–30 (Immediate): define scope, ownership, and minimum viable runbooks

• Name the CP-2(6) control owner and backups (GRC + SRE/Infrastructure).
• Publish the organization-defined list of mission/business functions in scope, with business owner sign-off. ¹
• Document current primary and alternate processing/storage sites per system.
• Draft failover and restoration runbooks for the highest-impact function first.
• Create the CP-2(6) evidence packet structure (folders, naming, retention).

Days 31–60 (Near-term): validate alternate site capability and security parity

• Confirm replication, dependencies, and access paths work in the alternate environment.
• Add sustainment procedures (monitoring, incident response, change control while in alternate mode).
• Run a tabletop exercise and capture results, issues, and remediation tasks.
• Formalize a recurring evidence cadence in your GRC system (Daydream or equivalent): runbooks current, tests performed, issues tracked.

Days 61–90 (Stabilize): run functional tests, close gaps, and make it repeatable

• Run functional tests that demonstrate actual transfer steps and restoration steps.
• Close high-risk gaps (missing dependencies, missing approvals, unclear triggers).
• Update documentation to match what the team actually did during tests.
• Prepare an assessor-ready narrative: scope → architecture → transfer → sustainment → restoration → evidence.

Frequently Asked Questions

Does CP-2(6) require a separate physical data center?

No. It requires an alternate processing and/or storage site that can take over defined functions and sustain operations through restoration. A second cloud region or separate environment can qualify if it meets your continuity needs. ¹

We can restore from backups. Is that enough for CP-2(6)?

Backups alone usually support restoration, but CP-2(6) is about planned transfer to an alternate site with minimal or no loss of continuity and sustained operations until primary is restored. Document how continuity is maintained, not just how data is recovered. ¹

What does “organization-defined mission and business functions” mean in practice?

You must explicitly list which functions you are planning to transfer and sustain at alternate sites, and keep that list controlled and approved. Auditors will ask to see the list and how it maps to systems and runbooks. ¹

How do we prove “minimal or no loss of operational continuity” without citing specific RTO/RPO in the policy?

Define internal continuity objectives, then show the transfer and sustainment plan can meet them through tests, incident records, or exercise results. Keep sensitive targets internal, but make the execution evidence clear and repeatable. ¹

Do we need to test failback (return-to-primary), or is failover testing enough?

CP-2(6) explicitly includes sustaining continuity through restoration to the primary site, so you should document and test restoration steps. At minimum, run a controlled restoration validation and capture evidence. ¹

What if a third party provides our alternate site (managed DR, cloud, colocation)?

Treat the third party as part of your control boundary: retain contracts/SLA terms relevant to continuity, confirm your runbooks align to their operational model, and keep test evidence that includes their role and timestamps.

Footnotes

1. NIST SP 800-53 Rev. 5 OSCAL JSON