Resize/extend RAID partition in Windows Server 2016

Published on: November 16, 2019

This article introduces how to resize RAID partition in Windows Server 2016, how to extend RAID 0/1/5/10 partition on Server 2016 without losing data.

To many administrators, it is not an easy task to resize raid partition in Windows 2016 server. Some raid arrays are built with 2 disks, some are built with 3 or even more disks. Some people want to extend system partition on a raid array, some want to increase size of a data volume. It seems complicated. In addition, many people are not sure whether it requires breaking array, also worry about system and data safety while shrinking and extending raid partition. In fact, it is easy to reallocate partition on raid array if you use right tool and follow correct steps.

How to resize RAID partition without any software

Firstly you should know, to Operating System and NIUBI Partition Editor, there's no difference if you use physical hard disk or raid array virtual disk. In most cases, you can resize raid partitions like physical disk partition. No matter what type of array with any brand of raid controller.

What you should concern is that whether there's free space in any partition on the same raid array. The same array means Disk 0, 1, etc that are shown by Windows Disk Management or NIUBI Partition Editor. To most of servers, there's free unused space in one of the raid virtual partitions. If the entire disk is full, follow the steps in last section.

Windows Server 2016 native Disk Management tool has Shrink Volume and Extend Volume functions, which can help resize part of partitions without losing data. However, both functions have many limitations, so Disk Management is not the best tool to help resize raid partition in Windows 2016 server.

The most common issue is, Disk Management can neither shrink FAT32 partition, nor extend a partition by shrinking any other one. Only when you want to shrink a NTFS partition to create new, or extend a NTFS partition by deleting the right contiguous volume, you can resize raid partition in Windows 2016 server without third party software.

How to extend RAID partition without rebuilding array

In most of servers, there's free space in at least one of virtual partitions on the same raid array, so you can you shrink it to get Unallocated space and then add to other partition that you want to expand. Open Windows Disk Management, if there's free unused space in D or other data volume, follow the steps to extend raid system partition in Windows Server 2016:

  1. Download NIUBI Partition Editor, right click the right contiguous partition D: (or E: in some server) and select "Resize/Move Volume", in the pop-up window, drag left border towards right or enter an amount in the box of Unallocated space before.
  2. Right click system partition C: and select "Resize/Move Volume" again, drag right border towards right in the pop-up window to combine the contiguous Unallocated space.
  3. Click Apply on top left to execute, done. (Any operations before this step only work in virtual mode.)

If you want to get free space from non-adjacent volume, there's an additional step to move Unallocated space before adding to C drive.

Video guide

No matter you want to extend RAID 0, 1, 5, or 10 partition with any brands of raid controller, as long as there's free space on the same raid array, follow the same steps above. Same raid array is shown the same with physical disk and numbered as Disk 0, 1, 2, etc.

Don't break raid array or do any other operation to raid controller. After shrinking and extending raid partitions, Operating System, programs and everything else keep the same with before, except partition size.

How to expand RAID array without losing data

If there's no available free space on the same raid array, what to do? It depends on your own raid type.

To hardware RAID 1, you cannot increase size of this raid by replacing with larger disks one by one and rebuilding the array. If you do like this you'll get the same size raid, additional space can only be used to create another array with your raid controller. In that case, you'll see a new and separated disk in Disk Management.

Steps to extend RAID 1 partition in Windows Server 2016 when this raid is full:

  1. Build a new RAID 1 with 2 larger disks.
  2. Right click the front position of original raid 1 disk and select "Clone Disk".
  3. Select the new raid disk and click Next.
  4. Edit the size and location of the partitions in destination disk, starting from the last partition one by one.
  5. Click the option to turn off computer after clicking Apply to take effect.
  • This operation requires server rebooting.
  • After copy complete, change BIOS to boot from the new RAID 1.
  • If you cannot attach 2 raid at the same time, you may copy old RAID 1 to a physical disk, and then copy again to the new RAID.

Video guide

To hardware RAID 5, you can increase its size easily. But before this, you'd better check the brand and model of your raid controller, confirm it has the ability to rebuild raid 5 array without losing data. If yes, follow the steps to extend RAID 5 partition in Windows 2016 server when this raid is full:

  1. Replace with larger disks or add more same size disk and rebuild the array.
  2. Additional space will be shown as Unallocated on the end of original raid array. Combine Unallocated space to the partition(s) that you want to expand.

If your raid controller cannot rebuild array without losing data, you have to follow the steps above to copy.

Comparing with other utilities, NIUBI Partition Editor is much safer and faster because of its unique Virtual Mode, Cancel-at-well, 1-Second Rollback technologies and file-moving algorithm. Besides shrinking, extending and copy disk partitions, it helps move, merge, convert, defrag, hide, wipe partition, scan bad sectors and much more.