How to Create NAS Mirror Backup to Sync Files to Another NAS

What is mirror backup? How to perform NAS mirror backup for file sync or data protection? This article will provide all the information you need and 2 ways to sync NAS to NAS.


By Delia Updated on November 30, 2022

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What is NAS mirror backup

A mirror backup is an identical copy of the source data as the name suggests, and NAS mirror backup refers to creating a mirror backup of NAS to another NAS (or other storage devices), which is usually achieved by file sync.

Mirror backup copies your files & folders to the destination with the original structure and format - you can get access to the backup directly instead of keeping an image file just in case.

Since it includes literally everything without any compression, it requires more storage space than other backup methods, but the changes made to the source data are also automatically (even in real time) reflected in the destination directory, which is very convenient for collaboration or off-site work.

Synology DS216 NAS

Practical applications of NAS mirror backup

Simply put, if you want to keep the latest and intact copy of NAS for direct use, NAS mirror backup is a smart choice. It’s easy to imagine its advantages in following situations:

• There’s an on-going job that needs to be done by different people on different devices;
• You want to keep the data on two NAS exactly the same for information consistency;
• You want to give the data on NAS an extra insurance to prevent accidental data loss or corruption.

In such cases, you can sync NAS to NAS instead of copying and transferring those files manually.  

What tools can be used to create NAS mirror backup

To create NAS mirror backup, the first thing you should prepare is an effective tool that can sync data between NAS and even other storage devices.

If you are using Synology NAS and want to mirror it to another Synology, you could consider downloading specialized tools from Synology Download Center to do a Synology mirror backup, Synology Drive Server is an example. Similarly, you can use Hybrid Backup Sync to backup QNAP to QNAP.

But if you are tired with the brand restrictions and want more powerful functions, AOMEI Backupper Standard is a good choice. It’s a backup & sync program with complete features and intuitive interface. Even a new user of it can acquaint the operation easily. 

Besides, it is free to create a NAS mirror backup with AOMEI Backupper. The high compatibility allows you to sync NAS to NAS or many other devices with ease.

Now let me show you the detailed steps to sync files between two NAS.

Method 1. Mirror NAS to another NAS or other devices via freeware

In AOMEI Backupper Standard, you can achieve the goal of creating NAS mirror backup by using file sync. Comparing with other sync software, the sync feature of AOMEI Backupper Standard has its own advantages. 

It allows you to synchronize files and folders to other locations including local disk, external hard drive, another computer on the network, NAS, removable USB flash drive and so on; it can be used combing with other practical features, such as schedule backup.

Download and install AOMEI Backupper to proceed.

Download Freeware Win 11/10/8.1/8/7/XP
Secure Download


1. Click Sync on the left sidebar and then select Basic Sync. You can enjoy more advanced sync modes if you upgrade to Professional edition:

Real-Time Sync: Auto sync any changes made to source NAS to target NAS in real time.
Mirror Sync: Always keep the files in target NAS exactly the same as in source NAS.
Two Way Sync:  Sync any changes in the source NAS or target NAS to the other side mutually.

File Sync

2. Input a Task Name for your NAS mirror backup to make a distinction between it and other backups. Click Add Folder, then select Share/NAS in the popping out window.

Share Nas

3. Click Add Share or NAS Devices. Input IP address, username and password of the NAS you want to mirror.

Select Synology Or Qnap Nas

4. Click the small down arrow beside destination select box, choose Select a network location and specify the target NAS in the same way.

Schedule: To perform a sync task (except for real-time sync) automatically, you need to set up a schedule on basis of Daily, Weekly or Monthly. In advanced editions, you can also choose Event triggers or USB plug in.

Select A Cloud Drive

5. Tap Start Sync button to begin the sync. When it is done, click Finish to quit the interface.

File Sync Complete

If you want to manage the folders that are applied with Basic Sync, you can find the task in Home page and click its icon with three stripes to expand the menu.

Note: Every time you execute an existing sync task, the source directory will be compared with the last mirror backup, any changes and newly added files will be synchronized to the target directory, while the deleted files won’t.

Useful feature you may need

As cloud storage is becoming more and more popular, AOMEI offers users its own cloud - AOMEI Cloud. After you sign up for an AOMEI account, you can use 1TB storage for free within 15 days. To backup files to AOMEI Cloud, just click Backup > Cloud Backup.

Cloud Backup

Method 2. Sync data between Synology NAS via Synology Drive Server

If you are using Synology NAS, you can install the latest DSM (DiskStation Manager) and download Synology Drive Server or Cloud Station from Download Center as an alternative, then run the tool on your host and client Synology NAS servers.

Take Synology Drive Server as an example. It is a centralized file sharing and syncing service that allows you to access the most updated files on multiple Synology NAS client devices. To do this seamlessly, one NAS device should be chosen as the host server, and the rest of the paired Synology NAS devices will act as client devices.


1. To sync files between the centralized NAS server and the client Synology NAS devices, the first thing you should do is establishing connections - enter the IP address, username, and password of the host Synology NAS device.

Synology Drive Server Enter Password

 2. Choose the remote and local shared folders that you want to sync, check Enable and click Apply button.

Synology Drive Server Choose Remote Folder

 3. When the setup process has been completed, a new connection will show in sync tasks for you to manage.

Synology Drive Server Finish

4. Now you can create sync tasks with the connected NAS, or click + button to add another new NAS following the steps above.


  • This method only applies to Synology NAS with the latest DSM.

  • For problems like cannot connect to the host Synology NAS device, you can refer to this tutorial for more details.


Compared with ordinary backup, mirror backup has its own characteristics and advantages to save you a lot of time and energy if used properly.

To create a NAS mirror backup means to sync data between two NAS - you can achieve it by some sync tools. So far as I tried, the File Sync feature of AOMEI Backupper Standard is one of the best solutions. It’s quick and safe with fewer restrictions and practical auxiliary functions, like Schedule. And you can enjoy the sync feature totally for free.

Not only NAS to NAS, AOMEI Backupper Standard also supports you to sync files between computers, sync OneDrive Automatically, sync local folder to Google Drive and so on.

Delia · Editor
Delia owns extensive experience in writing technology-related blog posts, and has been a part of AOMEI since 2020 to provide expertise in data security and disaster recovery. She works with Windows operating systems, SQL databases, and virtualization platforms such as VMware and Hyper-V, specializing in troubleshooting and advising on data protection and migration.