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The 3-2-1 Backup Strategy That Finally Made Sense: One NAS, One Cloud, One Mount

#cloud #hardware #infrastructure

I lost a hard drive last year. 18 months of photos, gone. That's when I implemented a serious 3-2-1 backup strategy.

The pieces:

  • 1 NAS at home (mirrored, gives me 1 copy + redundancy)
  • 1 cloud backup (B2 / S3 / Wasabi Cloud at minimum)
  • 1 USB drive for offline snapshots

But the workflow that makes it work in practice: mount the cloud as a real drive letter so my backup software can see it as just another disk.

What is 3-2-1?

The classic backup rule:

  • 3 copies of your data (the original + 2 backups)
  • 2 different media types (e.g., local disk + cloud)
  • 1 offsite (the cloud)

The 1 offsite is the most important. A fire, a burglary, a ransomware attack — all threaten both copies if they're both at home. Cloud backup is the only way to survive those scenarios.

My setup

Layer What Cost
Primary 2x 4 TB NAS mirror at home $240 one-time
Backup 1 Backblaze B2, 4 TB $20/月
Backup 3 USB SSD, snapshots monthly $120 one-time
Mount ScsDriver + rclone serve webdav $9.99/yr

The mount is the key — it lets my backup software treat the cloud as just another drive letter.

The mount setup

Backblaze B2 doesn't speak WebDAV natively. To mount it via ScsDriver, I run a local WebDAV server backed by rclone:

rclone serve webdav b2:my-bucket --addr :8080 --user backup --pass mypassword
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Then ScsDriver mounts http://localhost:8080/ as drive letter B:.

Now my Windows backup software (Duplicati, Veeam Agent for Windows, etc.) sees:

  • C: → local disk
  • N: → NAS mirror
  • B: → B2 cloud (via WebDAV mount)

Same workflow for all three layers.

Why this matters

Without the mount, my backup software would need separate plugins for each cloud provider. With the mount, the backup software just sees a drive letter and backs up. One tool, three destinations.

This is huge because:

  1. Tool simplicity — one backup tool, not three
  2. Same retention policy — apply the same 30-day / 90-day rule to all backups
  3. Easy verification — browse B:\ like a regular drive, verify the backup

Performance

Backup target Speed Time (1 TB backup)
Local disk (C:) 200 MB/s 1h 23m
NAS (N:) 100 MB/s 2h 47m
B2 via WebDAV mount (B:) 30 MB/s 9h 16m

The cloud is slower (encryption + upload + transit). For daily incremental backups (typically 5-10 GB), it's not bad — 5-10 minutes.

What I'd change

The 9-hour full backup to B2 is too long. Two options:

  1. Initial seed via B2 Fireball: ship Backblaze a hard drive, they upload it for you. ~$80 per 4 TB. After that, only incrementals go over the network.
  2. Reduce backup frequency: full backup weekly, not daily. Daily = incrementals only.

I do weekly fulls. Daily incrementals. Total weekly backup time: ~12 hours (B2 full + 6 daily incrementals).

Cost breakdown

  • Backblaze B2 (4 TB): $20/mo
  • ScsDriver: $9.99/yr
  • USB SSD: $120 one-time
  • rclone: free

Total monthly: $21 + ScsDriver prorated. Not cheap, but my 18 months of photos are not getting lost again.

Reference

3-2-1 doesn't have to be hard. Mount the cloud as a drive letter, point your backup software at it, sleep well at night.

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