Create an ECS instance by using a custom or shared image - Elastic Compute Service

This topic describes how to use a custom image to quickly create Elastic Compute Service (ECS) instances that have the same operating system, applications, and data. This helps improve the O&M efficiency of your business in the cloud.

Prerequisite

A custom image exists in the account and region in which you want to create an instance. For more information, see Custom image overview.

If no custom images exist in the account or region in which you want to create an instance, perform the operations that are described in the following table based on your business scenarios.

Scenario	Operation
You have an image on an on-premises device.	Import the on-premises image to Alibaba Cloud as a custom image. For more information, see Import an image.
You have a custom image in another region.	Copy the custom image to the region in which you want to create an instance. For more information, see Copy a custom image.
You have a custom image in another account.	Share the custom image with the account that you want to use to create an instance. For more information, see Share a custom image.
You have an instance or snapshot from which you can create a custom image.	Create a custom image from an instance Create a custom image from a snapshot

Procedure

Go to ECS console - Images.
In the top navigation bar, select the region and resource group of the resource that you want to manage.
On the Custom Images or Shared Images tab, find the image that you want to use and click Create Instance in the Actions column.
The region and the image are automatically specified. Configure other parameters, such as Billing Method and Instance Type, based on your business requirements.
Note
If the custom image that you selected contains one or more data disk snapshots, the same number of data disks are automatically created from the snapshots during the ECS instance creation.
For more information, see the "Parameters" section of the Create an instance on the Custom Launch tab topic.

What to do next

If you increase the capacity of an existing data disk when you create the ECS instance, you must log on to the instance to extend the partitions and file systems for the changes to take effect. For more information, see Extend the partitions and file systems of disks on a Linux instance and Extend the partitions and file systems of disks on a Windows instance.
Note
If you increase the system disk capacity and the cloud-init and growpart utilities are installed on the custom image, the root partition of the system disk automatically extends when the instance is created. For example, if you use a 20 GiB custom image on which the cloud-init and growpart utilities are installed to create an instance and you set the system disk size of the instance to 100 GiB, the root partition of the system disk automatically extends to 100 GiB when the instance is created. If the root partition fails to extend, resolve the issue based on the cause of the failure. For more information, see the I created an ECS instance from a custom image and specified a system disk capacity that is larger than the image size. However, the actual system disk capacity of the ECS instance is the same as the image size. What do I do? section of the "FAQ about images during instance creation" topic.
If you add new data disks when you create the instance, you must initialize the data disks before you can use them. For more information, see Initialize a data disk.