Backup and disaster recovery, explained
Backup and disaster recovery (BDR) is how a business protects its data and gets working again after something goes wrong. Backup is the copy: files, email and systems saved somewhere safe. Disaster recovery is the plan and the work of restoring those copies so people can do their jobs again, after anything from a dead drive to ransomware.
I'm Igor Dobrovolskiy, founder of As-Built IT in Raleigh. Before starting the company, I helped lead the technical recovery after a cyberattack across about 90 locations and roughly 10,000 employees.
So yes, I have opinions about backups. Loud ones, usually at parties, which is why I get invited to fewer parties.
If your firm's current backup plan is the USB drive in Gary's desk drawer, keep reading. Gary, you too. Bring the drive.
On this page: The difference · The jargon · 3-2-1 rule · Ransomware · Backup types · What to back up · Testing · Real recoveries · Mistakes · Questions
Backup vs disaster recovery: what's the difference?
Backup makes the copies, and disaster recovery uses them to get the business running again. One is a spare tyre, the other is knowing how to change it in the rain (I can do one of those).
Definitions follow IBM's guide to backup and disaster recovery.
What BDR means, and the jargon you'll hear
BDR is short for backup and disaster recovery, because IT people will abbreviate anything that holds still long enough. A “BDR backup” usually means a backup set up so it can restore a whole system, not just a few files. Here's the rest of the vocabulary, minus the eye-rolling.
- RPO, recovery point objective: how much recent work you can afford to lose, an hour or a day
- RTO, recovery time objective: how long you can afford to be down before it really hurts
- Offsite copy: a backup kept somewhere other than your office, so one bad day can't take both
- Immutable backup: a copy that can't be changed or deleted, not even by ransomware
Those first two come from IBM's definitions, and they're the two numbers worth deciding before you buy anything. Gary's drawer drive, for the record, has an RTO of “whenever Gary is back from lunch”.
The 3-2-1 rule: how many backup copies is enough?
The 3-2-1 rule is the standard answer. CISA, the US Cybersecurity and Infrastructure Security Agency, recommends keeping 3 copies of important files, on 2 different types of storage, with 1 copy kept offsite.
In practice that means the working copy on your server, a second copy on separate storage, and a third copy in the cloud. Gary's drawer drive counts as one copy. It does not count as a strategy.
Left: three copies in three places. Right: a backup nobody can change, which is the part ransomware hates.
Why ransomware changed the rules for backups
Ransomware doesn't just lock your files; it goes looking for your backups too. A backup that sits on the same network, with the same passwords, can be scrambled right alongside everything else.
That's why modern backups are immutable: once written, they can't be changed or deleted for a set time. Ours at As-Built IT work that way, so an attack on your network can't reach them. It's the one time in IT where being stubborn is a feature.
Full, incremental or differential: the three kinds of backup
Most backup systems mix three kinds of backup, and the names are scarier than the ideas. Here's the whole thing in one breath (please don't actually hold your breath).
- Full: a complete copy of everything, slow to make and simple to restore
- Incremental: only what changed since the last backup of any kind, fast and small
- Differential: everything changed since the last full backup, a middle ground that grows until the next full one
Definitions from Sharp's guide to backup types. Good backup software mixes them for you, so nobody has to remember which Tuesday was the full one. Where the copies live matters more: a copy in the office restores quickly, and a cloud copy survives when the office doesn't.
What design and build firms need to back up
A design or build firm needs to back up its servers and shared file storage, Microsoft 365, staff laptops and desktops, and finished project archives. Miss one, and that's the one that breaks, because IT has a sense of humour and it's terrible.
- Servers and shared storage: where the Revit models, CAD files and drawings actually live
- Microsoft 365: email, OneDrive, SharePoint and Teams, which syncing alone doesn't protect
- Staff laptops: the work that never quite made it back to the server
- Project archives: finished jobs you may need years later, long after Gary forgets the folder name
Field work adds one more wrinkle: files saved on a job-site trailer laptop belong in the backup too. We cover the cloud side of all of this in cloud backup for business, including the bits nobody remembers until they're gone.
Why a backup you've never restored is a guess
A backup only counts once you've restored from it. Until then it's a very confident guess wearing a progress bar.
Recovery testing means restoring from your backups on purpose, to prove the files and systems come back. We do recovery testing as part of our backup and disaster recovery services, because the worst possible time to find a broken backup is the day you need it.
What I've seen when backups meet a real disaster
The recovery I helped lead after that cyberattack meant restoring critical IT infrastructure across about 90 locations. It took more than fixing technology: coordinating the recovery, rebuilding the network, restoring connectivity and helping people get back to work.
At a construction company of about 75 people hit by ransomware mid-project, the clean backups were the whole ballgame. We isolated the systems, restored files from those clean copies and brought the most urgent systems back first.
And at an engineering firm, a failed shared drive held CAD drawings, calculations and weeks of active work. The most recent usable backup is what saved it, which is a sentence I'd like you never to need.
Backups are the cheap part. Being able to restore them on a bad day is the part that matters.
Backup mistakes we see most often
- Keeping the only backup in the same room as the server
- Treating OneDrive or SharePoint syncing as a backup
- Never testing a restore until the day it's needed
- Leaving backups where ransomware can reach them
And the classic: one USB drive, in one drawer, belonging to one Gary. We love Gary. We do not love the drawer.
Backup and disaster recovery questions
What is backup and disaster recovery?
Backup and disaster recovery (BDR) is the combination of copying a business's data to safe places and having a plan to restore it and get people working again after data loss, an outage or a cyberattack.
What's the difference between backup and disaster recovery?
Backup is the copy of your data. Disaster recovery is the plan and process of using those copies to get systems and people working again.
What does BDR stand for?
BDR stands for backup and disaster recovery. A BDR backup is usually one set up to restore whole systems, not only individual files.
What is the 3-2-1 backup rule?
Keep 3 copies of important files, on 2 different types of storage, with 1 copy offsite, as recommended by CISA.
Is OneDrive or SharePoint a backup?
Not on its own. Syncing copies changes everywhere, including deletions and files scrambled by ransomware, so a separate backup is still needed.
Where to go from here
If your firm is in Raleigh or the Triangle, see how our backup and disaster recovery services work, or book a free 30-minute call.
Bring your questions, your list of servers and, if it comes to that, Gary's drawer drive. We'll be gentle with it.
About the author
Igor Dobrovolskiy founded As-Built IT in Raleigh in 2026 after 15 years in IT, including helping lead the technical recovery after a major cyberattack at a global enterprise. He has strong feelings about USB drives in drawers.