:INFO
The 3-2-1 Rule Is Non-Negotiable
The 3-2-1 backup rule has been the professional standard for decades because it addresses three independent failure modes: 3 copies of your data means one corruption doesn't destroy everything; 2 different media types means a hardware failure class doesn't take out two copies at once; 1 off-site copy means a fire, flood, or theft can't take everything at once. Your Pi's external drive is one copy. A local backup is two. An encrypted off-site copy is what saves you when the worst happens.


:COUNTER.half
3 Copies

:PATH
Install restic and Initialize a Local Repository
Install restic from your package manager: sudo apt install restic. Create a directory for your local backup repository: sudo mkdir -p /mnt/backup/restic-local. Initialize the repository with restic -r /mnt/backup/restic-local init — restic will ask you to

:PATH
Run Your First Backup and Verify It
Back up your NAS data directory: restic -r /mnt/backup/restic-local backup /mnt/nas. Restic will scan, deduplicate, encrypt, and write the data. When it finishes, run restic -r /mnt/backup/restic-local snapshots to see a table of completed snapshots with 

:PATH
Configure rclone for Off-Site Storage
Install rclone: sudo apt install rclone. Run rclone config and follow the interactive prompts to add Backblaze B2 as a remote (the free tier covers the first 10 GB, and costs are low beyond that). Name the remote b2 and create a bucket in the Backblaze co

:PATH
Automate with a Cron Job
Create a backup script at /usr/local/bin/backup.sh that exports your restic password as an environment variable, runs the local backup, runs the remote backup, and sends the exit code somewhere you'll notice (a simple curl to a healthcheck URL, or an emai

:PATH
Do the Restore Test Right Now
This is the step most people skip and later regret. Choose a directory from your backup — something meaningful, not a throwaway test file. Run restic -r /mnt/backup/restic-local restore latest --target /tmp/restore-test --include /mnt/nas/important-folder

:QUOTE [quotetype:personal]
A backup you haven't restored from isn't a backup, it's a hope.


:NOTE
Store your restic repository password in at least two places: a password manager and a printed copy kept off-site. If you lose the password, restic's AES-256 encryption means your backup data is mathematically unrecoverable. No support ticket will help you. The password is as important as the backup itself.


:INFO
What Comes Next
With reliable backups in place, most people quickly want to run more than one service on their Pi — a media server, a notes app, a home automation hub. Installing each one manually creates a maintenance nightmare. Docker changes that equation completely, letting you deploy any service in minutes and tear it down just as fast.


:SLATE
992

:LINK
https://restic.readthedocs.io
restic — fast, secure, efficient backup program