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The 3-2-1 Backup Rule & Data Backup Strategies

Backing up your data is essential to protect against hardware failure, accidental deletion, ransomware, and disasters. The 3-2-1 backup rule is a widely recommended strategy for ensuring your data is safe.

What is the 3-2-1 Backup Rule?

  • 3: Keep at least three copies of your data (the original + two backups).
  • 2: Store the copies on two different types of media (e.g., hard drive, NAS, cloud, USB, DVD).
  • 1: Keep at least one backup offsite (e.g., cloud storage, another physical location).

Why Follow the 3-2-1 Rule?

  • Protects against hardware failure, theft, fire, flood, and other disasters.
  • Reduces risk of losing all data due to a single point of failure.
  • Ensures you can recover from accidental deletions or ransomware attacks.

Backup Strategies for NAS Users

1. Local Backups

  • Use your NAS to back up computers and devices on your network.
  • Use built-in NAS apps or third-party tools (e.g., rsync, Time Machine, Windows Backup).

2. NAS-to-NAS or NAS-to-External Drive

  • Back up your NAS to another NAS or an external USB drive.
  • Many NAS systems support scheduled replication or external drive backups.

3. Offsite & Cloud Backups

  • Use cloud backup services (e.g., Backblaze B2, Wasabi, Google Drive, Dropbox) to store encrypted copies of your data.
  • For sensitive data, encrypt before uploading to the cloud.
  • Alternatively, rotate external drives and store one offsite.

4. Automated Backups

  • Schedule regular, automated backups to avoid forgetting.
  • Test your backups by restoring files occasionally.

Tips for Reliable Backups

  • Automate: Set up scheduled backups so you don’t have to remember.
  • Monitor: Enable notifications for failed backups.
  • Test Restores: Periodically restore files to ensure your backups work.
  • Versioning: Keep multiple versions of files to recover from accidental changes or deletions.
  • Encryption: Encrypt backups, especially if stored offsite or in the cloud.

Example Backup Plan for Home NAS

  1. Store all important files on your NAS.
  2. Back up NAS to an external USB drive weekly.
  3. Sync critical folders to a cloud service (encrypted) nightly.
  4. Test restores every few months.

More Resources


A good backup is your last line of defense. Don’t wait for disaster—start backing up your data today!

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