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
Disk resizing is an operation that extends disks to larger sizes. When the capacity of a disk does not meet your storage requirements, you can resize the disk to increase the storage space to accommodate more data.
Flowchart on resizing a disk
Resize a disk in the Elastic Compute Service (ECS) console.
For more information, see Step 1: Resize a disk to extend its capacity.
Connect to the ECS instance to which the disk is attached and extend the file systems and partitions of the disk in the operating system to take advantage of the added storage space. For more information, see Connection method overview.
Before you extend the file systems and partitions of the disk, decide on what resize operations to perform based on the following factors: whether the disk is partitioned, the partition style, and the new disk size. The following table describes the operations.
Operation
Procedure
Unpartitioned disk (raw disk): Directly extend the file systems.
Extend the partitions and file systems of disks on a Linux instance
Partitioned disk
If 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, convert the disk into a GPT disk and then extend its partitions and file systems.
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 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 (system disk) 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: 2,048 GiB
Data disk: 32,768 GiB
Enhanced SSDs (ESSDs), ESSD AutoPL disks, ESSD PL-X disks, standard SSDs, and ultra disks support the preceding capacity limits. Basic disks (retired previous-generation disks) can be up to 500 GiB in size when they are used as system disks and 2,000 GiB in size when they are used as data disks. For more information, see the EBS limits section of the "Limits" topic.
For example, an instance uses a 40 GiB ESSD as the system disk. When you resize the system disk, the new size of the system disk must be larger than 40 GiB but cannot exceed 2,048 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 need to 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 Block storage devices.