Synology Active Backup for Business (ABB) is a free backup solution included with DSM that lets you protect unlimited Windows PCs, servers, and VMware/Hyper-V virtual machines without buying per-device or per-seat licences. Combined with a Synology NAS, it replaces paid solutions like Veeam Community Edition or Acronis Cyber Backup for home labs and small businesses. At no software cost beyond the hardware. Microsoft 365 (Exchange Online, SharePoint, Teams, OneDrive) backup is also included via a separate ABB module.
In short: Install Active Backup for Business from Package Center on the NAS, then deploy the Windows agent on each PC you want to protect. Create a backup task per device, set a schedule and retention policy, and verify with a test restore. For most home users with 2-4 PCs, setup takes about 45 minutes. The biggest failure point is under-sizing storage. Plan for at least 3× the data you're backing up to accommodate retention versions.
Requirements and Supported Configurations
Active Backup for Business requires:
- NAS: Any Synology NAS running DSM 6.2.3 or later. x86 NAS models (DS225+, DS425+, DS925+, DS1525+ and above) have better performance for concurrent backups. ARM models (DS223, DS124) can run ABB but are limited to lower concurrency and slower deduplication processing.
- Backup target: A Btrfs-formatted volume for deduplication to work properly. If your volume is ext4, ABB still works but you lose global deduplication. Each backup version stores full data. Format a new volume as Btrfs when setting up or check Storage Manager > Volume for existing format.
- PC (Windows): Windows 7 SP1 through Windows 11. Windows Home editions are supported for PC backup only (not server features). The agent must be installed with administrator rights.
- Server/VM: Windows Server 2008 R2 through 2022, VMware ESXi 6.0+, Hyper-V on Windows Server 2012+ or Windows 10/11 Pro with Hyper-V enabled.
Step 1. Install Active Backup for Business on the NAS
On DSM, open Package Center and search for Active Backup for Business. Click Install. When prompted, choose the Btrfs volume as the storage destination for backup data. If you don't have a Btrfs volume, go to Storage Manager > Volume > Create and select Btrfs as the file system during volume creation. Btrfs is required for the global deduplication engine that makes ABB storage-efficient. Without it, each incremental backup wastes space storing duplicate blocks across devices.
After installation, open Active Backup for Business from the App menu. The first run activates your licence. This is free and just requires a Synology account (or can be done without one via a signed EULA click). No payment or registration key is needed.
Step 2. Install the Windows Agent on Each PC
From the Active Backup for Business portal on DSM, go to PC > Add Device and download the Windows agent installer (ActiveBackupforBusinessAgent.exe). Copy this to each PC you want to protect. Via USB, network share, or email.
Run the installer on the PC with administrator rights. During installation, enter the NAS hostname or IP address and DSM admin credentials. The agent connects back to the NAS over TCP 443 (HTTPS) or TCP 5510 (a dedicated ABB port. Check your router/firewall settings if the connection fails). The NAS must be reachable from the PC at installation time.
Once the agent connects, the PC appears in the ABB portal under PC > Devices. If you're backing up multiple PCs on the same network, repeat this on each machine.
Step 3. Create and Configure a Backup Task
In the ABB portal, click Create Task for the PC you want to back up. Configure:
- Backup mode: Entire device backs up all volumes including the OS. Volume lets you select specific drives. For most PCs, Entire device gives the most complete protection and enables bare-metal restore.
- Schedule: Continuous backup (every 15 minutes) is available but aggressive for home use. Scheduled mode with daily backups at off-peak hours (e.g. 2:00 AM) is the practical choice. For a work PC with critical files, consider hourly during business hours using a custom schedule.
- Retention policy: Set a retention period (e.g. 30 days) or a maximum number of versions (e.g. 30 restore points). ABB deduplication means old versions don't linearly multiply storage. Shared data blocks are stored once. Even so, plan conservatively: if a PC has 500GB of data, allocate at least 1.5TB of NAS storage per device to hold 30 days of versioned backups with room for growth.
- Backup destination: Select the Btrfs volume. Use sub-folders per device if backing up multiple PCs (ABB creates them automatically under a folder named after the device hostname).
Click Apply to save. The first backup will be a full image and may take several hours. Or longer for large drives. Subsequent incremental backups typically complete in under 30 minutes for a standard desktop.
NBN upload speed note: If backing up over your home network (wired or Wi-Fi), speeds depend on your local Ethernet connection, not your NBN speed. A wired Gigabit connection can saturate a 5400RPM NAS drive at ~100MB/s. The NBN speed only matters for remote backup (backing up a laptop at a cafe or office to your home NAS). On a standard NBN 100 plan with ~20Mbps upload, backing up 100GB of data remotely takes roughly 12 hours. For remote use cases, schedule large initial backups when the device is back on the local network first, then let remote sync catch daily deltas.
Step 4. Test a Restore
A backup you haven't tested is a backup you don't have. After the first successful backup completes, perform at least one restore test before relying on the system.
File-level restore: In the ABB portal, select the device, choose a restore point, and browse to a specific file or folder. Click Restore to > Original location (or a custom location). The restored file should appear on the PC within a minute. This is the most common recovery scenario. A user accidentally deletes a file or folder.
Bare-metal restore: This recovers an entire PC from scratch after a hardware failure or OS corruption. Create a Recovery Media USB drive from the ABB portal (go to Recovery Portal > Create Recovery Media). Boot the target PC from the USB, connect to the NAS, select the backup version, and restore. For a working office PC, test this on spare hardware at least once a year to confirm the process works end-to-end. A backup that can't restore is worse than useless. It creates false confidence.
Step 5. Back Up Microsoft 365 (Optional)
Active Backup for Microsoft 365 is a separate module within ABB that backs up Exchange Online email, OneDrive, SharePoint, and Teams data to your NAS. Install it from Package Center by searching for Active Backup for Microsoft 365.
In the M365 module, connect your Microsoft 365 tenant using an admin account with appropriate API permissions (Global Reader at minimum, delegated permissions for user data). Once connected, create backup tasks per service (email, OneDrive, etc.) and set a schedule. M365 backup runs over the internet. It pulls data from Microsoft's servers to your NAS. On a standard NBN 100 plan, a full initial backup of a 10-user M365 tenancy with 50GB of mailbox data will take several hours; configure it to run overnight.
This is particularly relevant for Australian SMBs using Microsoft 365. Microsoft's SLA covers service availability, not data retention. If you accidentally delete a SharePoint document and notice after Microsoft's 93-day recycle bin window, the data is gone. Your own ABB backup extends retention indefinitely at no per-user software cost.
Storage Sizing for Active Backup
ABB's deduplication engine is effective at reducing storage for similar-content machines (e.g. multiple PCs with the same Windows installation), but don't over-rely on it for planning. A conservative sizing rule: allocate 2-3× the total uncompressed data you're backing up to hold 30 days of retention with room for full OS images.
Example: 3 PCs, each with 500GB of used storage = 1.5TB total source data. Budget 4-5TB of NAS storage for comfortable 30-day retention with deduplication. A DS425+ ($899 at Mwave) populated with 4× 4TB WD Red Plus drives in SHR (~12TB usable) gives ample room with budget for future growth. For single PC backup at home, a DS225+ ($585) with 2× 4TB drives (4TB usable in RAID 1) is sufficient for most desktop libraries.
All Synology NAS purchases from Australian retailers like Mwave, PLE, Scorptec, and Umart include Australian Consumer Law protections. If the unit fails within a reasonable timeframe, you're entitled to repair, replacement, or refund regardless of the standard 1-year warranty.
Related reading: our NAS buyer's guide, our Synology brand guide, and our NAS explainer.
Free tools: Backup Storage Calculator and NAS Sizing Wizard. No signup required.
Is Active Backup for Business really free?
Yes. Active Backup for Business is included with DSM at no cost. There's no per-device licence fee, no subscription, and no user cap. The only cost is the NAS hardware and drives. Synology has confirmed this model applies to unlimited PCs and servers. Even in commercial deployments. Compare this to Veeam Essentials (~$800 AUD for 3 nodes) or Acronis Cyber Backup (~$70/device/year) to understand the value.
Can I back up a Mac with Active Backup for Business?
No. Active Backup for Business only supports Windows PCs, Windows Server, VMware, and Hyper-V. For Mac backup to a Synology NAS, use Time Machine over SMB. DSM supports macOS Time Machine natively without any additional software. You can run both ABB (for Windows) and Time Machine (for Mac) simultaneously on the same NAS.
Does Active Backup work if the NAS and PC are on different networks?
Yes, with some configuration. The Windows agent communicates with the NAS over TCP 443 (HTTPS). If the PC is offsite (a laptop at work, for example), the NAS must be accessible remotely. Via QuickConnect, DDNS with port forwarding, or VPN. On Australian NBN connections with CGNAT, direct port forwarding may not work. See the remote access guide for CGNAT workarounds. Backup speed over remote connections is limited by the NAS's upload speed (NBN plan upload Mbps).
How does Active Backup deduplication work?
ABB uses block-level deduplication across all backed-up devices. If two PCs have the same Windows system files, those blocks are stored once and referenced by both backup sets. This is most effective for multiple similar machines (office PCs with the same OS build) and less effective for diverse content like video libraries. Deduplication requires a Btrfs-formatted volume. On ext4, each backup version stores full data without deduplication. Check Storage Manager to confirm your volume is Btrfs before deploying ABB for multi-device backup.
What's the difference between Active Backup and Hyper Backup?
Active Backup for Business is designed for backing up external devices (PCs, servers, VMs) to your NAS. Hyper Backup is for backing up data from your NAS to an offsite destination (cloud storage, remote NAS, USB). They serve different roles in a complete backup strategy: ABB protects your PCs, Hyper Backup protects the NAS itself. For a complete 3-2-1 backup strategy, you'd use both: ABB backs up your PCs to the NAS, Hyper Backup backs up the NAS to cloud or offsite storage.
How long does the first backup take?
The first backup is a full disk image, so time depends on data size and network speed. On a local Gigabit Ethernet connection, a 500GB PC drive typically backs up in 2-4 hours. Wi-Fi backups take longer depending on signal strength. 5GHz Wi-Fi at close range is comparable to wired; 2.4GHz or weak signal can drop to 10-30MB/s. The agent runs in the background with low CPU priority, so the PC stays usable during backup. Subsequent incremental backups are much faster. Typically 5-30 minutes for daily changes on a standard desktop.
Need to protect your NAS data offsite after setting up PC backup? Read the 3-2-1 backup strategy guide to understand how Hyper Backup complements Active Backup for Business in a complete data protection plan.
3-2-1 Backup Strategy Guide →