You can resize a system disk or a data disk to extend its capacity. This topic describes
how to resize a disk for a Windows Elastic Compute Service (ECS) instance when the
instance is running.
Prerequisites
The requirements described in the following table are met before you can resize a
disk online for a Windows instance.
Resource |
Requirement |
Instance |
- The instance is I/O optimized.
- The instance does not run Windows Server 2003.
- The instance is not an ecs.ebmc4.8xlarge, ecs.ebmhfg5.2xlarge, or ecs.ebmg5.24xlarge
instance.
- The instance is in the Running (Running) state.
- The version of the Red Hat virtio-scsi driver is later than 58011. For more information
about how to check the version of the Red Hat virtio-scsi driver and update the driver,
see Update Red Hat virtio drivers of Windows instances.
|
Disk |
- The disk is in the In Use (In Use) state.
- The disk is an enhanced SSD (ESSD), a standard SSD, or an ultra disk.
- The disk is formatted with New Technology File System (NTFS) file systems.
- After you renew a subscription instance and downgrade its configurations, you cannot
resize the subscription disks on the instance for the remainder of the current billing
cycle.
- When you resize a disk of a specific category, the specified new disk capacity cannot
exceed the maximum single-disk capacity allowed for the disk category. For more information,
see the "Elastic Block Storage (EBS) limits" section in Limits.
Notice
A disk in the master boot record (MBR) partition format cannot be resized to 2 TiB
or larger. To resize an MBR disk to larger than 2 TiB, you can use one of the following
methods:
|
Background information
The following table describes the resources used in the examples of this topic.
Resource |
Description |
Image used by the instance |
Windows Server 2012 R2 64-bit |
System disk |
The system disk is resized from 40 GiB to 60 GiB and is formatted with NTFS file systems.
|
Data disk |
The data disk is resized from 40 GiB to 60 GiB and is formatted with NTFS file systems.
|
Step 1: Create a snapshot
Create a snapshot for a disk to back up disk data before you resize the disk.
- Log on to the ECS console.
- In the left-side navigation pane, choose .
- In the top navigation bar, select a region.
- Find the instance whose disk you want to resize and click the instance ID.
- On the Instance Details page, click the Cloud Disk tab.
- Find the disk that you want to resize and click Create Snapshot in the Actions column.
- In the Create Snapshot dialog box, enter a snapshot name, specify tags, and then click
Create.
- Click the Snapshot tab to view the snapshot.
When the snapshot is created, 100% appears in the Progress column corresponding to the snapshot. You can proceed to perform subsequent operations.
Step 2: Resize the disk in the ECS console
- On the Instance Details page, click the Cloud Disk tab.
- Find the disk that you want to resize and choose in the Actions column.
To batch resize disks, log on to the ECS console by using your Alibaba Cloud account
and choose in the left-side navigation pane. On the Disks page, select the disks that you want
to resize and click Resize Disk in the lower part of the page. Disks that are attached to the same instance cannot
be resized together.
- On the Resize Disks page, select Online Resizing and set the Size after Resize parameter.
The specified Size after Resize value must be greater than the current capacity.
- Verify the price. Read and select ECS Service Terms, and then click Confirm.
- Read the notes, click I have read the notes. Resize, and then complete the payment.
Notice
- After you resize the disk in the ECS console, you must resize the partitions and file
systems of the disk within the instance before you can use the new capacity of the
disk.
- If you use Logical Volume Manager (LVM) to manage partitions of the disk, you must
use LVM to resize the partitions and file systems after you resize the disk in the
console. For more information, see Resize an LV by using LVM.
Step 3: Resize the file system of the system disk or data disk partition
After you resize a disk of an instance in the ECS console, the file systems of the
disk partitions are not resized. You must connect to the instance to extend the file
systems. The system and data disks are resized from 40 GiB to 60 GiB and are formatted
with NTFS file systems. The following steps describes how to resize the file system
of a system disk partition.
- Log on to the instance. For more information, see Connect to a Windows instance by using a password or key.
- On the Windows Server desktop, right-click the Start icon and select Disk Management.
- In the Disk Management dialog box, choose to view the unallocated disk capacity.

Disk 0 is the system disk and Disk 1 is a data disk.
- Right-click the blank space in the Disk 0 section and select Extend Volume...
Note If you resize the file system of a data disk partition, right-click the blank space
in the data disk (such as Disk 1) section. If your disk has multiple partitions, we recommend that you resize the
partition that is adjacent to the left of the unallocated partition. Otherwise, Windows
changes the selected basic disk into a dynamic disk.

- Extend the volume as instructed in Extend Volume Wizard.
The new space is automatically added to the original volume, as shown in the following
figure.

After the disk is resized, check whether the new capacity of the disk is consistent
with the specified capacity.
- If the file system size is increased to the specified value and business programs
on the instance can run normally, the file system is resized.
- If the file system size is not increased to the specified value, use the snapshot
that you created in Step 1 to roll back the disk.
Step 4: (Optional) Create a partition on the data disk
If you want to create a partition in the new disk space, perform the following steps:
- Log on to the instance. For more information, see Connect to a Windows instance by using a password or key.
- On the Windows Server desktop, right-click the Start icon and select Disk Management.
- In the Disk Management dialog box, choose to view the unallocated disk capacity.

Disk 0 is the system disk and Disk 1 is a data disk.
- Right-click the blank space in the Disk 1 section and select New Simple Volume...
- Extend the volume as instructed in New Simple Volume Wizard.
A partition is created in the new disk space.