Building a Personal Digital Archive That Lasts: A Practical 3-2-1 Foundation

Most people today have a growing collection of digital material that actually matters—photos, documents, letters, scans, audio recordings, the accumulated record of a life. And most of it is scattered. Computers, phones, cloud services, email accounts, external drives gathering dust in drawers. No clear plan for how it’s protected, organized, or what happens to it long-term.

A personal digital archive is an intentional response to that mess.

It’s not just storage. It’s knowing where important material lives. Being able to find and use it later. Making sure it survives accidents, hardware failures, fires, floods, hurricanes—the disasters you don’t think will happen to you. And time itself: those physical photos sitting in boxes are fading and deteriorating right now. A digital archive captures them in a way that halts further decay. Here’s the part people don’t think about until it’s too late: making it understandable and accessible to someone else if you’re not around to explain it.

At the core of any robust personal digital archive is a simple truth: an archive that isn’t reliably protected isn’t really an archive. It’s a collection of files you’re planning to lose.

This post describes the foundational infrastructure for a durable personal digital archive. It’s built around a simple 3-2-1 protection structure that makes the whole thing trustworthy, resilient, and actually future-proof.

Why most “backups” aren’t enough for an archive

When people say they “have a backup,” they usually mean one of three things: files synced to iCloud or Google Drive, a single external hard drive (probably disconnected right now), or a vague sense that “the computer backs itself up somehow.”

Each of these helps with certain problems. None of them is sufficient for preserving a meaningful archive over years or decades.

A single external drive protects against computer failure—but not theft, fire, or the flood you didn’t think would happen. Cloud sync protects against device loss, sure, but it’ll also faithfully sync the moment you accidentally delete something or your files get corrupted. And none of these gives you much confidence that recovery will actually work when you desperately need it to.

What’s missing is deliberate structure.

The 3-2-1 structure (as archive infrastructure)

The 3-2-1 approach means three copies of important data, on two different types of storage, with one copy stored somewhere else entirely.

Here’s the thing: many people who do some backup are actually running a 2-2-0 setup. Two copies on two devices, zero copies outside the home. That’s fine for “oops I deleted something.” It is absolutely not sufficient for an archive you’re trying to preserve over decades.

In this context, 3-2-1 isn’t just a backup rule—it’s the structural foundation that lets an archive grow safely and predictably.

A brief word about ransomware

You’ll see ransomware mentioned when people talk about backups, so let me clarify something that confuses everyone.

Ransomware is malicious software that encrypts your files with a key you don’t have, demands payment to unlock them, and often spreads automatically once it gets onto a computer. Paying the ransom frequently doesn’t even work.

Now, this guide also recommends encrypting your computer and drives. Same word, completely different thing.

Protective encryption (FileVault, BitLocker) keeps strangers out. It locks your data when the device is off, unlocks automatically when you log in. Ransomware locks you out, even though you’re already logged in, by encrypting your files a second time with a key it won’t give you.

For most individuals, the odds of a ransomware attack are relatively low. The consequences if it happens are devastating. Ransomware can make your entire archive unreadable, encrypt any backup drive that’s plugged in at the time, and quietly propagate through sync-based cloud backups. A proper 3-2-1 foundation limits the damage and gives you a way to recover without paying criminals.

The practical foundation: setting up a simple 3-2-1 archive system

What follows is a concrete, pragmatic way to build this infrastructure using tools that are widely available and not terribly expensive.

Step 1: Create a single “Archive” folder

Everything depends on this.

Make one clearly named folder that holds everything you truly care about. Call it “Archive.” Put it in your home directory—on Mac that’s /Users/yourname/Archive, on Windows it’s C:\Users\yourname\Archive.

Inside the Archive: photos and videos, important documents, scans, letters, notes, personal history. Anything you would genuinely be upset to lose permanently. If it’s not in the Archive, it’s not guaranteed to survive.

This folder isn’t just a backup source. It’s the living core of the personal digital archive.

One important assumption: you need the disk space

This setup assumes your computer has enough room to hold the Archive. In practice, archives grow—photos get digitized, documents get scanned, you add audio and video over time.

Before you commit to this, confirm there’s enough space today and room to grow over the next few years. If that’s not true, see “When the Archive can’t live on the computer” below.

Step 2: Encrypt the computer itself (required)

The primary copy of the Archive lives on your computer. If the computer gets lost or stolen, your archive is exposed unless the drive is encrypted.

Turn on full-disk encryption. FileVault on Mac, BitLocker on Windows. This protects the Archive automatically, requires zero daily effort, and is much safer than trying to encrypt individual folders. Once full-disk encryption is on, the Archive itself doesn’t need separate encryption.

Step 3: Copy #1 — the working archive

The Archive folder on your computer is Copy #1. This is the version you work with, add to, and grow over time.

Step 4: Copy #2 — a local backup on an encrypted external SSD

This copy protects against computer failure, accidental deletion, software problems, and ransomware (as long as the drive is unplugged most of the time, which it should be).

A modern external SSD works well for this. Something like a SanDisk Extreme Portable SSD (1 TB) is fine.

Preparing and encrypting the drive

On macOS, use APFS (Encrypted). Open Disk Utility, go to View → Show All Devices, select the device itself (top-level entry, not the partition), and erase using APFS (Encrypted) with GUID Partition Map. If APFS doesn’t show up as an option, you can force it through Terminal:

diskutil list
diskutil eraseDisk APFS "BackupSSD" GPT /dev/diskX

On Windows, you’ll use BitLocker To Go for removable drives. Plug it in, reformat as NTFS if needed, right-click the drive and select “Turn on BitLocker,” set a password, save the recovery key somewhere safe, and let it encrypt the whole drive.

Setting up the periodic backup

Use a real backup tool—Carbon Copy Cloner on Mac, Macrium Reflect on Windows. Create a saved task: source is your Archive folder, destination is the Archive folder on the external SSD, one-way sync from computer to drive.

From then on: plug in the SSD, unlock it, click Run, wait for it to finish. Weekly or monthly is plenty.

Step 5: Copy #3 — automatic off-site backup

This is what protects you from fire, flood, theft, or total loss of your home.

Backblaze makes several products. For this, you want Backblaze Computer Backup (not B2 Cloud Storage, not B2 Overdrive).

Install it, confirm the Archive folder is included in the backup, exclude the external SSD. Once it’s set up, it runs in the background. You don’t think about it.

When the Archive can’t live on the computer

Sometimes the Archive is just too big to fit comfortably on your computer. If that’s the case, use a two-external-drive setup instead:

External Drive A is the master Archive (your working copy). External Drive B is the local backup of Drive A.

Configure Backblaze to back up External Drive A. Exclude Drive B. This still gives you 3-2-1: three copies, two types of devices, one off-site.

Step 6: Use a password manager

Backups protect data. Passwords protect access.

Use something like Bitwarden to store: the encryption passwords for your external drives, your Backblaze account password, your email password (critical for recovery). Optionally your computer login password.

Do not store passwords inside the Archive or write them on a sticky note attached to the drives.

Step 7: Archive organization and file naming (summary)

An archive is most useful when things are named consistently. The pattern I recommend is simple:

Category_Date_Description.ext

Category comes from a small list you define. Date uses whatever precision you have—YYYY-MM-DD if you know the exact day, YYYY-MM if you only know the month, just YYYY if that’s all you’ve got, YYYY-Q1 for “sometime in early 2003.”

Examples: Photo_1984-06_FamilyPicnic.jpg, Document_2003-Q4_TaxReturn.pdf, Scan_1997_Passport.pdf.

Full guidance on structure and taxonomy is its own post.

Step 8: Prepare for future handoff

A personal archive should make sense even if you’re not there to explain it.

Add a short README.txt inside the Archive. Print a note and store it with the external drives. Tell at least one person you trust that this exists—that there’s a local backup, an off-site backup, and a password manager involved.

What this foundation enables

Once this is in place, the higher-value work becomes safe and meaningful. Photo scanning, document digitization, metadata enrichment, file organization, restoration, growth over time.

There’s not much point enhancing material that isn’t protected.

Final thoughts

A personal digital archive isn’t something you finish. It’s something you establish, protect, and grow.

The structure described here—anchored by 3-2-1—provides the durability that makes everything else possible. The goal isn’t just avoiding data loss. It’s ensuring that the record of a life remains intact, usable, and meaningful. Today and years from now.