Help Center> Elastic Volume Service> User Guide> Changing the EVS Disk Type (OBT)

Updated on 2024-03-18 GMT+08:00

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Changing the EVS Disk Type (OBT)

If the performance of an existing disk no longer meets your service requirements, you can change the disk type to improve the disk performance.

This function is in the OBT. Submit a ticket to apply for the OBT.

**Table 1** Constraints on the disk type change
Phase	Description
Before the change	The disk type can be changed only when the disk status is Available or In-use. The disk type cannot be changed when any snapshot of the disk is being deleted. Changing the disk type may affect the disk performance, so change the type during off-peak hours.
During the change	Some operations cannot be performed on the disk. Such operations include creating snapshots, creating backups, expanding the disk capacity, rolling back data from a snapshot, restoring data from a backup, attaching or detaching the disk, deleting the disk, transferring the disk, and creating an image from the ECS. Changing the disk type may take several hours or even longer, and cannot be stopped. The time depends on the throughput, storage space, and original disk type at the time of the change. In rare cases, the change may fail due to resource problems. In this case, you are advised to perform the change again. You can have a maximum of 10 disks with their types being changed at the same time. The OS cannot be changed if you are changing the disk type of a system disk.
After the change	In rare cases, the disk type may fail to be changed due to a backend issue. If this happens, try again later.

For details about the disk type change, see Table 2.

**Table 2** Supported changes between disk types
Source Disk Type	Description
Extreme SSD V2	Can be assigned with a different IOPS.
Extreme SSD	Can be changed to Ultra-high I/O or General Purpose SSD.
General Purpose SSD V2	Can be assigned with a different IOPS or throughput or both.
Ultra-high I/O	Can be changed to Extreme SSD or General Purpose SSD.
General Purpose SSD	Can be changed to Extreme SSD or Ultra-high I/O.
High I/O	Can be changed to Extreme SSD, Ultra-high I/O, or General Purpose SSD.
Common I/O (previous generation product)	Can be changed to Extreme SSD, Ultra-high I/O, General Purpose SSD, or High I/O.

Read and write operations on the disk are not affected.

Log in to the management console.
Under Storage, click Elastic Volume Service.
The disk list page is displayed.
In the disk list, locate the target disk, click More in the Operation column, and choose Modify Specifications.
The Modify Specifications page is displayed.
Select a disk type from the drop-down list.
The system shows you the new price based on your selection.
Click Submit.
The disk list is displayed, and the disk status is Changing disk type, indicating that the disk type is being changed. After the disk type changes to the target type, the operation is successful.