IT Disaster Recovery Planning

IT Disaster Recovery Planning

Overview

IT Disaster Recovery (DR) planning ensures technology systems can be restored and resume critical functions following a disruption.

Key Concepts

Recovery Objectives

| Term | Definition | |------|------------| | RTO | Recovery Time Objective - maximum acceptable downtime | | RPO | Recovery Point Objective - maximum acceptable data loss | | MTD | Maximum Tolerable Downtime - business threshold |

Tiered Recovery

| Tier | RTO | RPO | Strategy | |------|-----|-----|----------| | 1 | <1 hour | Near zero | Active-active, sync replication | | 2 | 1-4 hours | <1 hour | Hot standby, async replication | | 3 | 4-24 hours | <4 hours | Warm standby | | 4 | 1-3 days | <24 hours | Cold standby |

DR Strategies

Data Backup

• Full, incremental, differential
• On-site, off-site, cloud
• Retention policies
• Encryption requirements

Replication

Synchronous:

• Zero data loss
• Performance impact
• Limited distance

Asynchronous:

• Near-zero data loss
• Less performance impact
• Greater distance flexibility

Site Strategies

Hot Site:

• Fully operational
• Real-time data sync
• Fastest recovery
• Highest cost

Warm Site:

• Partially operational
• Periodic data sync
• Moderate recovery time
• Moderate cost

Cold Site:

• Basic infrastructure
• Manual data restore
• Slowest recovery
• Lowest cost

Cloud-Based DR

• DRaaS (Disaster Recovery as a Service)
• Multi-region deployment
• Auto-scaling
• Pay-per-use

DR Plan Components

Documentation

• System inventory and dependencies
• Recovery procedures
• Contact information
• Vendor information
• Network diagrams

Procedures

• Activation criteria
• Notification process
• Failover steps
• Failback procedures
• Testing protocols

Roles and Responsibilities

• DR coordinator
• Technical teams
• Business liaisons
• Vendor contacts

Testing Program

Test Types

| Type | Frequency | Scope | |------|-----------|-------| | Tabletop | Quarterly | Walkthrough | | Component | Monthly | Individual systems | | Integrated | Semi-annual | Multiple systems | | Full | Annual | Complete failover |

Test Objectives

• Validate procedures
• Measure RTO/RPO
• Identify gaps
• Train personnel

Documentation

• Test plan and scope
• Results and metrics
• Issues identified
• Remediation actions

Cloud Considerations

• Multi-region architecture
• Availability zones
• Cloud provider SLAs
• Data residency
• Egress costs