Disaster Recovery (DR)

6.7 Explain business continuity concepts.

📘CompTIA ITF+ (FC0-U61)

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Disaster recovery is a plan and process that an organization uses to recover IT systems, data, and access after a disaster. Disasters could include hardware failure, software issues, cyberattacks, natural disasters affecting data centers, or accidental deletion of data. The goal is to minimize downtime and restore services as quickly as possible.

Key areas for DR in IT include:

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1. Data Restoration

Data restoration is the process of bringing back lost or corrupted data from backups.

• How it works in IT:
  • If a company’s database crashes, IT can restore it from a backup stored on-site (like a company server) or off-site (like a cloud backup).
  • Files, emails, and system settings can also be restored to their previous state.
• Important concepts:
  • Backup types: Full backup (all data), Incremental backup (only changes since last backup), Differential backup (changes since last full backup).
  • Backup locations:
    • Local – fast to restore but vulnerable to local disasters.
    • Off-site/cloud – safe from local disasters but may take longer to restore.
• Exam tip: Remember that data restoration is about recovering lost data using backups.

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2. Prioritization

Not all systems are equally critical. Prioritization helps IT decide what to restore first.

• Critical vs. non-critical systems:
  • Critical systems: Email servers, customer databases, payment systems.
  • Non-critical systems: Old archives, testing environments, non-essential apps.
• Why it matters in IT:
  • During a disaster, IT teams focus on restoring critical systems first to keep the organization running.
  • Example: A bank may restore online banking systems before internal reporting tools.
• Recovery Time Objective (RTO):
  • Maximum acceptable time that a system can be down.
  • Critical systems have short RTOs, non-critical systems can have longer RTOs.
• Exam tip: Prioritization ensures that the most important IT systems are restored first to reduce business impact.

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3. Restoring Access

Restoring access is about making IT systems available and usable again after a disaster.

• Steps in IT:
  1. Verify restored data – Ensure backup data is correct and not corrupted.
  2. Rebuild systems – Reinstall or configure servers and software if needed.
  3. Network access – Make sure users can log in and access files, applications, and services.
  4. Test functionality – Check that systems are working properly before fully reopening them to all users.
• Key point for exams: It’s not enough to just restore data; users and applications must actually be able to use the systems again.

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Putting It All Together

In a disaster recovery scenario, IT typically follows this workflow:

1. Identify the disaster – e.g., server failure or ransomware attack.
2. Prioritize systems – decide which systems must be restored first.
3. Restore data – recover from backups.
4. Restore access – rebuild systems, networks, and user access.
5. Test systems – ensure everything is working correctly.

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Quick Exam Memory Tips

• Data restoration = recover lost data from backups.
• Prioritization = restore critical systems first.
• Restoring access = make systems usable again for users and apps.