This topic describes what is disk resizing, the procedure on how to resize a disk, disk capacity limits, and charges for disk resizing. Both system disks and data disks can be resized.

Disk resizing

When the capacity of a disk does not meet your storage requirements, you can resize the disk by extending its capacity.

Procedure

Procedure
  1. Resize a disk that is attached to an Elastic Compute Service (ECS) instance in the ECS console.

    For more information, see Resize disks online for Linux and Windows instances.

  2. Connect to the ECS instance and extend the partitions and file systems of the disk in the operating system.
    Before you extend the partitions and file systems, you must decide on what extending operations to perform based on the following factors: whether the disk is partitioned, the partition format, and the new disk size.
    OperationReferences
    Unpartitioned disk (raw disk): Directly extend the file systems.Extend the partitions and file systems of disks on a Linux instance
    Partitioned diskIf the disk is resized to up to 2 TiB, directly extend the partitions and file systems.
    If the disk is GPT-formatted and is resized to more than 2 TiB, directly extend the partitions and file systems.
    If the disk is MBR-formatted and is resized to more than 2 TiB, you must convert the disk into a GPT disk and then extend its partitions and file systems.
    1. Convert MBR partitions into GPT partitions
    2. Extend the partitions and file systems of disks on a Linux instance or Resize the partitions and file systems of disks for Windows instances
Note In addition to resizing existing disks, you can also use the following methods to obtain more storage space.
  • Method 1: Create a disk, attach the disk to the ECS instance as a data disk, and then manually initialize the disk. For more information, see Create a disk.
  • Method 2: Replace the system disk with a large disk. For more information, see Replace the operating system of an instance.

Capacity limits

When you resize a disk, the new capacity must be greater than the existing capacity and can be up to the maximum capacity allowed for the disk. System disks and data disks are subject to different capacity limits.
  • System disk: 500 GiB
  • Data disk: 32,768 GiB
    Note An ESSD AutoPL disk, enhanced SSD (ESSD), standard SSD, or ultra disk can be up to 32,768 GiB in size. A basic disk (retired previous-generation disk) can be up to 2,000 GiB in size.

For example, assume that an instance has a 40 GiB system disk. When you resize this system disk, the specified new capacity must be greater than 40 GiB but cannot exceed 500 GiB.

Charges

When you resize a disk, you are charged for the incremental capacity by using the billing method used for the disk.
  • For a subscription disk, you must pay the price difference between the new capacity and the original capacity based on the remaining subscription duration.
  • For a pay-as-you-go disk, the new capacity takes effect immediately after the disk is resized, and the disk is billed on a pay-as-you-go basis for the new capacity.

If you have purchased Storage capacity units, they are automatically applied to offset the bills of pay-as-you-go disks. For more information, see EBS devices.