Synology Backup Strategy

October 25, 2025 - nas backup

This is my cheap backup strategy using two rotating HDDs.

One drive connects to your NAS in a USB enclosure. The other stays in an offsite location.
Every few weeks, you physically swap the two drives.
The NAS automatically backs up to whichever drive is connected each night, then turns it off afterward.

What you need

Synology NAS
- Hyper Backup
USB HDD enclosure
2 HDDs
2 HDD travel cases (optional but recommended)

How to set it up

The setup involves configuring the backup jobs in Hyper Backup and creating scheduled scripts to automate turning the USB drive on and off.

Step 1: Hyper Backup

Hyper Backup ties each task to a specific drive. So we need to create backup tasks for each drive.

General settings

Setting	Value
Backup Type	Folders and Packages
Backup Destination	Local Shared Folder or USB
Backup Version Type	Multiple versions
Enable task notification	Disabled
Compress backup data	Enabled
Enable backup rotation	Enabled (Smart Recycle)

Hyper Backup only runs one task at a time. By staggering the start times by one minute, we can control the order of tasks.

The last tasks are responsible for ejecting the HDD.
This is done by enabling Remove destination external device when backup task has successfully finished.

Task specific settings

HDD #	Task #	Name	Type	Schedule	Time
1	1	Data-1	Backup	Daily	3:00
			Integrity check	Sunday	5:00
	2	Documents-1	Backup	Daily	3:01
			Integrity check	Sunday	5:01
	3	Media-1	Backup	Daily	3:02
			Integrity check	Sunday	5:02
2	1	Data-2	Backup	Daily	3:00
			Integrity check	Sunday	5:00
	2	Documents-2	Backup	Daily	3:01
			Integrity check	Sunday	5:01
	3	Media-2	Backup	Daily	3:02
			Integrity check	Sunday	5:02

Step 2: Find out your USB device path

SSH into your Synology and run dmesg | grep usb.
Look for a line that says usb1, usb2 or similar. In my case it was usb2.

Step 3: Task Scheduler

This is where we make sure to only power the drives when needed. Two task turn the HDD on and one turns it off again. Sometimes the last Hyper Backup Task fails to eject the HDD, so we create a task to make sure it's powered off.

Go to Control Panel -> Task Scheduler -> Create -> Scheduled Task -> User-defined script.

Task #	Name	Schedule	Time	User	Script
1	Turn on USB HDD	Daily	2:55	root	`echo 0 > /sys/bus/usb/devices/usb2/authorized` `sleep 1` `echo 1 > /sys/bus/usb/devices/usb2/authorized`
2	Turn on USB HDD	Sunday	4:55	root	`echo 0 > /sys/bus/usb/devices/usb2/authorized` `sleep 1` `echo 1 > /sys/bus/usb/devices/usb2/authorized`
3	Eject and turn off HDD	Daily	5:30	root	`synousbdisk -umount usb2` `sleep 10` `echo 0 > /sys/bus/usb/devices/usb2/authorized`

This guide was tested on Synology DSM 7.2. The exact steps or command names may vary slightly on other versions.