> ## Documentation Index
> Fetch the complete documentation index at: https://doc.blueapi.ir/llms.txt
> Use this file to discover all available pages before exploring further.

# Disaster Recovery Plan and Procedures

> Failure classification, recovery procedures, RPO/RTO targets, and quarantine protocols for total site loss, storage loss, registry loss, and GPU cluster loss.

EMEP experiments run for hours or days on expensive GPU resources. Losing state mid-experiment is costly. This page defines the disaster recovery plan, failure classifications, and the decision flow for recovery versus abort.

## Recovery Objectives

| Objective                      | Target | Tracking ID |
| ------------------------------ | ------ | ----------- |
| Recovery Point Objective (RPO) | TBD    | OQ-009      |
| Recovery Time Objective (RTO)  | TBD    | OQ-009      |

These values are set per deployment tier during initial provisioning.

## Failure Classes

| Class             | Description                                   | Typical Cause                                 |
| ----------------- | --------------------------------------------- | --------------------------------------------- |
| Total site loss   | Complete unavailability of primary deployment | Datacenter failure, regional outage           |
| Storage loss      | Object store or database corruption           | Disk failure, operator error, ransomware      |
| Registry loss     | ModelRegistry metadata unavailable            | Database corruption, schema migration failure |
| Network partition | Split between control plane and GPU workers   | Switch failure, misconfigured firewall        |
| GPU cluster loss  | All GPU nodes unavailable                     | Power loss, thermal event, firmware bug       |

## Recovery Flow

```mermaid theme={null}
flowchart TD
    START([Failure Detected]) --> CLASSIFY[Classify Failure]
    CLASSIFY --> RECOVERABLE{Recoverable?}
    RECOVERABLE -->|YES| RETRY[Retry / Resume]
    RETRY --> VALIDATE[Validation Check]
    VALIDATE --> CONTINUE{Valid?}
    CONTINUE -->|YES| RESUME[Continue Experiment]
    CONTINUE -->|NO| ABORT[Abort + Preserve Logs]
    RECOVERABLE -->|NO| QUARANTINE[Quarantine Affected Resources]
    QUARANTINE --> INCIDENT[Incident Record]
    INCIDENT --> MANUAL[Manual Recovery Procedure]
```

A failure is recoverable if the experiment checkpoint, model weights, and registry metadata are intact. Validation checks hash integrity, registry consistency, and experiment state machine validity.

## Per-Class Procedures

### Total Site Loss

Fail over to the standby deployment. Restore from the latest backup. Replay experiments from the last checkpoint. All in-flight experiments are marked FAILED and must be resubmitted.

### Storage Loss

Restore the object store or database from backup. Run a consistency scan to identify artifacts with missing chunks. Re-download or re-merge artifacts that fail the scan. Experiments referencing intact artifacts may resume.

### Registry Loss

Restore the registry database from backup. Rebuild indexes from artifact manifests stored in the object store. Verify that every registered model has a corresponding artifact. Flag orphaned artifacts for review.

### Network Partition

If the partition heals within the task timeout, workers reconnect and resume. If the timeout expires, tasks are marked INCOMPLETE and rescheduled. GPU nodes that miss three heartbeats are marked unavailable.

### GPU Cluster Loss

Reschedule all active tasks to remaining GPU nodes. If no GPUs are available, queue tasks with a priority boost. When GPUs return, run a health check before marking them available.

## Quarantine Protocol

Affected resources are moved to a quarantine prefix with restricted access. The incident record includes failure class, timestamp, affected artifacts or nodes, recovery action taken, and operator identity.

## Cross-Links

* [Backup Strategy](/operations/backup-strategy)
* [Runbook](/operations/runbook)
* [GPU Health](/operations/gpu-health)