By Ivy / Last update July 14, 2022

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Can I Sync Synology NAS to External Devices?

I have a folder on the NAS called "Pictures". That folder has several subfolders. "Sorted" is all the finished and indexed stuff. There's "New pictures" and "2019 Unsorted" and "2018 unsorted" etc. And I want to sync the entire Picture folder to USB drive so when I sort name of pictures in the annual folders and drag them into the "sorted" folder, the sync-folder on the USB drive will replicate the changes.  

There was the "Shared Folder Sync" that seemed perfect, but it apparently only works NAS to NAS. Is there a simple program to sync Synology NAS to external USB drive? I'd really like it to be on the Synology to exclude any slowdowns on the network by syncing it via a computer.

Synology Sync to External Drive with USB Copy

In fact, there is a feature named USB copy to sync folders to external hard drive. Only USB or SD devices with file systems recognized by Synology NAS (eg: Btrfs (Linux), ext3, ext4, FAT, FAT32, exFAT, HFS, HFS Plus, and NTFS) are allowed for data copy.

To export data, it requires Synology NAS supports HFS+ file system. Learn more hardware specifictions for Synology NAS. After confirming it, follow the steps below:

1. Insert external USB or SD storage device to Synology NAS. And create a folder on it.

2. Install USB Copy at the Package Center and run it. Then, click Create icon (+) at the lower left corner and select copy task type - Data Export. It helps you export data from the DiskStation to the external USB or SD storage device. 

Create Data Export Task

3. Specify the task name, choose source and destination folders respectively in Synology NAS and external drive. Then, select a copy mode and corresponding settings.

  • Multi-versioned(default): This mode will create a folder every time the task runs and name with the run time. All source files will be fully copied to the destination.
  • Mirroring: This mode create a complete copy of source folder and all changes will be copied to the destination. 
  • Incremental:This mode copy newly added and modified source files every time this task runs.

Select Sync Settings and Mode

For the Multi-versioned mode, you are able to rotate backup versions from the earliest version, use smart recycle, or specify the rotation number.

  • Rotate from the earliest version: It will rotate backup versions when stored versions exceed the maximum limit. 
  • Smart Recycle: It will keep hourly versions from the past 24 hours, daily versions from the past 1 day to 1 month, weekly versions older than 1 month. And then, if the remaining versions till exceed the limit, it will delete the earliest versions.
  • Number of versions: It support maximum number between 1 and 65535 of versions to keep. Once the stored versions exceed the set number, it will delete the earliest versions.

Rotation Settings

4. Set the trigger time, USB plugged in, eject when copy completes, or enable schedule on daily or other frequencies.

Trigger Time

5 Tick the file types you want to copy or type filenames or extensions if you want to sync other file types. Then, click Apply and Run to copy folders from Synology NAS to external drive.

Run Synology Sync Folder to External Drive

Synology External USB Drive Not Detected - Fixed 

Sometimes, you may find the external USB drive not detected but don't know how to make it detected. Here are helpful tips you can try: 

# 1. Reboot Synology NAS. Turn off your NAS, unplug the power cord for 1 minute, remove your USB device, and repeat the step reversely. 

# 2: Check the Compatibility. As a matter of fact, not all external hard drive compatible with Synology NAS, hence, you need to the compatibility list for external hard disk, external USB drive, or other devices. 

# 3. Verify External hard drive. Disconnect the external drive and connect it to other USB 2.0 or 3.0 port, see if it's detected by Synology NAS. Or if you are worried about the external drive is damaged, try to replace with other external hard disks to sync folders.

# 4: Check the file system on external drive. For now, Synology claimed that only Btrfs (Linux), ext3, ext4, FAT, FAT32, exFAT, HFS, HFS Plus, and NTFS file system could be recognized on Synology NAS. For other file systems, you need to format it before using it for Synology sync external drive.

👉 To format external USB drive:

Go to System > Control Panel > External Devices, select the unrecognized external drive, click Format. Then, you will be asked to select format options, either entire disk or selected partition, and file sysem type (EXT 4 or FAT32). Choose the corresponding option and click OK to start the formating process.

Format External Drive Synology NAS

Easier Way to Perform Synology Sync Folder to External Drive

USB Copy feature is helpful for you to sync Synology folder to external drive, but it's limited, for example, not all Synology NAS modules support HFS+ file system, which is required for data export, Synology external USB drive not detected, etc. To avoid such problems, try powerful NAS synchronization software - AOMEI Backupper Professional.

With it, you can easily sync folders on Synology NAS in Windows XP, Vista, 7, 8, 8.1, 10, 11 (32-bit and 64-bit). It only requires the Synology NAS to be on and you know the Synology NAS address, username, and password. And you can enjoy the following advantages:

Rich sync methods: Basic Sync, Real-Time Sync, Mirror Sync and Two-Way Sync. The previous 3 sync methods are one-way file sync with different focuses. See differences between syncs to learn more. 
Set up a schedule sync task to automatically run, such as, daily, weekly, monthly, event triggers, and USB plugged in(sync folders automatically to USB when it's plugged in).
 Sync folders on multiple locations, such as, Synology NAS or QNAP NAS, network drive, external hard drive (HDD or SSD), USB flash drive, CD/DVD, etc.

To sync folder from Synology NAS to external hard drive, just refer to the following description. Please download AOMEI Backupper Professional and install it. For server users, try AOMEI Backupper Server

Download Free TrialWin 11/10/8.1/8/7/XP
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1. Launch AOMEI Backupper Standard after installation, click Sync > Basic Sync.

File Sync

2. Add Synology NAS and select the shared folder on it. Click Add Folder > Share/NAS > Add Share or NAS Devices, input the Network Path (IP address of Synology NAS), username, password and click OK

Add Folder

add share or NAS device

3. Choose the external USB drive to save all the folders from Synology NAS.

4. Click Schedule Sync and enable it, then select the schedule settings you like. You can also click Options to comment the sync task, enable email or SMS notification, verify the integrity of files in the destination during synchronization, etc. Then, hit Start Sync >> to perform Synology Sync to external hard drive easily. 

  • Daily, Weekly, Monthly: It is to sync files from every 1 hour to 6 hours in a day, or use weekly and monthly. 
  • Event triggers: It allows you to sync files at specific events, such as, system startup, system shutdown, user logon, or use logoff.
  • USB Plug in: It is capable of copying files automatically when USB drive plugged in. 

Schedule Sync Files

Wait for a while, your folders in Synology NAS will be synced immediately. Besides, you could sync external hard drive to Synology NAS.

Summing It Up

It’s quite simple to do Synology sync to external drive with AOMEI Backupper. In addition, AOMEI Backupper Professional offers you mirror sync, real time sync, and two way sync.

To prevent your Windows operating system and hard disk from any threats, like virus attack, ransomware, hardware failure and system crashes, it’s better to create a system image to external hard drive, migrate Windows 10 operating system to SSD, create WinPE bootable media, clone HDD to SSD without losing data, etc.