By Ivy / Last update December 13, 2021

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Can I Sync Synology NAS to External Devices?

“I bought an external dock to save the data of my NAS onto external hard disks, it works great with my old 2TB WD Green hard disks. Now my Synology NAS cannot detect my new 3TB WD Green hard disk, I tried to format it with exFAT and NTFS, with no success. Please help, thanks a lot.”

What should you do to perform Synology sync to external drive?


How to Make External Hard Disk be Detected on Synology NAS?

Sometimes, you will get the external USB drive not detected problem, you could try the following method as well.


# 1. Check the Compatibility

As a matter of fact, if your external drive is not compatible with Synology NAS, the external devices also can’t be detected. You could refer to the compatibility list for external hard disk, external USB drive, or other devices.


# 2. Check the file system on external drive

For now, Synology claimed that only these formats could be recognized on Synology NAS:

Btrfs (Linux), ext3, ext4, FAT, FAT32, exFAT, HFS, HFS Plus, and NTFS

Except for the above formats, any other unrecognized external drive have to be formatted before used on the Synology NAS.

If the external drive uses other formats and well connected with your Synology NAS, and please format it with Synology NAS.

Steps to format external drive with Synology NAS

Important: Please backup all files on the external hard drive before this formation, or you could lose it forever, and can’t recover it.

1. Please go to Control Panel > External Devices on the System section.

2. All the external hard disks will be listed here, select your unrecognized external drive and then click Format.

Format External Drive Synology NAS 

3. Choose format Entire disk (or Selected partition), choose the file system, and click OK to format the external hard disk.

Format External Drive Entire Disk 

★Tip: Synology NAS is capable of formatting the external drive with EXT4 and FAT32.

Then you could use the external devices on the Synology NAS named satashare[number] or usbshare[number]. for example, usbshare1, satashare1, etc.


# 3. Reboot Synology NAS

Reboot and reconnect your external drive or USB drive with the following steps:

1. Turn off your NAS.

2. Unplug the power cord for 1 minute.

3. Remove your USB device from the USB port on your NAS.

4. Turn on your NAS and connect your USB device to the USB port on your NAS.


# 4. Verify the External hard drive

You could use other USB 2.0 or 3.0 port to check, use the external drive to your computer, connect other external devices to Synology NAS to check if it can be detected, etc. To verify whether the external hard drive is damaged or not, if so please replace with other external hard disks to sync folders.

After Synology NAS recognizes the external hard drive, you could use Synology NAS to sync data to external drive.


Synology Sync to External Drive with USB Copy

In fact, there is a feature named USB copy to sync folders to external hard drive. USB Copy will copy files and folders between Synology NAS and external USB/SD storage device. How to copy folders from Synology NAS to external USB drive, please refer to the guide:

1. Install USB Copy at the Package Center and create a folder on the external USB drive.

2. Click Main Menu to run USB copy, click Create icon (+) at the bottom left corner > Data Export.

3. Specify the task name, choose folders in Synology NAS, set the external drive as the destination, and customize the copy mode.

Copy Folder From Synology NAS To External Drive 

4. Set the trigger time and file filter, And then click Apply to create this copy task. Press Run to copy folders from Synology NAS to external drive.


Best Free NAS Sync Software - AOMEI Backupper Standard

Another powerful free NAS synchronization software - AOMEI Backupper Standard is highly recommended to sync folders from Synology NAS to external devices as well. It’s available in Windows XP, Vista, 7, 8, 8.1, 10, including all editions, 32-bit and 64-bit.

With its concise interface, reliable performance, and the comprehensive sync features, you could do:

  • Sync Two Synology NAS or QNAP NAS with simple clicks.

  • Sync folders to multiple destinations, like local disk, external hard drive (HDD or SSD), USB flash drive, CD/DVD, network share or NAS, even clouds.

  • Set up a schedule sync task to automatically run.

  • Sync folders automatically once the USB plugged in. Available in AOMEI Backupper Professional and other advanced editions.

Download Freeware

Win 10/8.1/8/7/XP

Secure Download

To show how it works to sync folder from Synology NAS to external hard drive, just refer to the following description:

1. Launch AOMEI Backupper Standard after installation, click Sync > Basic Sync.

Basic Sync 

2. Press + Add Folder > Share/NAS > Add Network Location > Input the Network Path (IP address of Synology NAS) > click OK to add Synology NAS, choose the folders you want to sync.


Add Network Location

3. Choose the external drive (or USB drive) as destination to save all the folders from Synology NAS.

NAS To External Drive Sync 

4. Hit Start Sync >> to perform Synology Sync to external hard drive easily. 

✍Options: It allows you to comment the sync task, enable email or SMS notification, verify the integrity of files in the destination during synchronization, etc.
✍Schedule: It enables you to set the sync task run daily, weekly, monthly, USB plug in, event triggers. Please upgrade to AOMEI Backupper Professional or other editions to enjoy the last two features. Event triggers could help you trigger the sync task via the four events, User logon, user logoff, system startup, system shutdown.

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.

For Windows server users, please try AOMEI Backupper Server to enjoy more features.