How to Mirror HDD to another Hard Drive in Windows Server 2012?

August 18, 2017

When you need to mirror or upgrade HDD to another hard drive in Windows Server 2012 (R2), AOMEI Partition Assistant will help you to clone disk effectively and securely. It is suitable for Windows Server 2008/2008 R2/2003 as well.


“With 1 TB HDD (hard disk drive), my Windows Server 2012 machine used to work well. But recently, the HDD is filled up with files and the running speed of it is very slow. I am going to replace the HDD with a large hard drive to get more space and higher operating speed. But in the meantime, I want to keep all the applications and the operating system on the original HDD. What should I do if I want to achieve this goal?”


Although the Windows built-in features of “copy” and “paste” is able to put operating system and applications to the new hard drive, the machine will not boot and some applications will not work normally. Therefore, to the question mentioned in above scenario, mirroring Windows Server 2012 HDD is the best way to reach the goal. In fact, Windows Server 2012 disk mirroring not only for reserving all the data on original disk, but also for avoiding data loss if accident occurs.

How to mirror Windows Server 2012 HDD to another hard drive?

Windows Server 2012 disk mirroring is a time-saving and simple way to keep the same content on new hard drive. The next part will present how to clone Windows Server 2012 HDD to another hard drive.

The indispensable items for Windows Server 2012 mirroring 

In advance of Windows Server 2012 disk mirroring, you have to prepare following indispensable items:

Good Server cloning software: Good cloning software can assistant you to clone Windows Server HDD easily and safely; it is important to find proper Server cloning software.

A hard drive with enough space: In order to mirror Windows Server 2012 HDD successfully, the new hard drive has to own larger or equal space at least to the used space on the original disk.

A readable source HDD: To enable Windows Server 2012 mirroring, the HDD shall be readable.

With the essential items, you can achieve the goal of replacing HDD with hard drive in Windows Server 2012 and keep the same content on new hard drive.

Clone Windows Server 2012 HDD with AOMEI Partition Assistant

AOMEI Partition Assistant Server is the best cloning software for Windows Server 2012. With strong functions and use-friendly interface, it can help you to perform Windows Server 2012 mirroring.

Here are things you should do before cloning HDD to new hard drive:

  • In order to copy HDD/SSD smoothly, Check error on partition on the HDD at first.

  • It is a good choice to backup HDD just in case that some accidents occur.

Detailed guide for Windows Server 2012 mirroring with AOMEI Partition Assistant are as following:

Step 1: To make Windows Server 2012 mirroring, you should install AOMEI Partition Assistant and launch it. Then, right click the disk that you want to copy and choose “Copy Disk”.

PS: There are two methods for Windows Server 2012 mirroring: “Disk Copy Quickly” and “Sector-by-Sector Copy”. The former just clone the used space and it allows you to adjust partition size; the latter clone all the sectors of source disk and partition size is unchangeable; the latter costs more time than the former. It is highly recommended to choose “Disk Copy Quickly” due to flexible partition size and higher efficiency.

Select the Disk

Step 2: You can choose the way that you like in following window.

Copy Disk Quickly and Sector by Sector Copy

Step 3: Select destination hard drive and click “Yes”. If the target disk is SSD, it is reasonable to tick the box before “Optimize the performance of SSD”.  

Select Target Disk

Step 4: You can edit partitions in following window. Make your choice and click “Next”.

PS: There are three optionsfor you:

Copy without resizing partitions”: The size of every partition will be as same as the original size. The rest space of target disk will be omitted.

Fit partitions to entire disk”: The size of partition will be adjusted to entire destination disk automatically in accordance with the scale of source disk.

Edit partitions on this disk”: The size of partition can be adjusted manually according to your demand.

Edit Partition

Then an important “Note” will present in pop-up window, keep it in mind. Click “Finish”.

Boot System Operating

Step 5: Check the pending operations and click “Apply” to implement Windows Server 2012 mirroring.

Windows Server 2012 Mirroring

Click “Proceed” and follow the instruction presenting in pop-up window: restart your computer to complete the pending operation in the PreOS Mode.

PS: If there is unallocated space on the destination hard drive after cloning in Windows Server 2012 (R2), you can create new partition with AOMEI Partition Assistant Server.


Just within few steps, AOMEI Partition Assistant manages to implement Windows Server 2012 mirroring. It is useful and powerful. And if you want to keep system while replacing HDD/ SSD with new hard drive, the feature “Migrate OS to SSD” can help you to implement Windows Server 2012 mirroring on system. As powerful server cloning software, apart from Windows Server 2012(R2), AOMEI Partition Assistant Server is compatible with Window Server 2003/2008 (R2) as well. It is not only a cloning tool, but also a partition manager. Based on partition, it owns various functions such as resize partition, merge partition and split partition and so on.