Generally, the Cloud Migration tool migrates ECS instances by creating snapshots and generating custom images. If you have created the corresponding target ECS instances, you can migrate the source instances directly to the target instances. This speeds up the instance migration process because you do not need to create snapshots or generate custom images.


  • Contact technical support to obtain the related permissions.
  • Prepare one or more target ECS instances in the target Alibaba Cloud region. The number of target ECS instances is the same as the number of source instances. The source ECS instances must be in stopped state.
  • Back up the data in the system disks of the target instances. This is recommended because the system disks will be replaced after the migration.


To migrate a source instance to its target instance, follow these steps: If you want to migrate multiple instances, you can repeat the steps detailed in this procedure as needed until all instances are migrated.

  1. Download the Cloud Migration tool (V1.2.9.7 or later).

  2. Configure the client_data file and set target_instance_id in extra.

    Note By default, the disk of the target instance is an ultra disk. If the disk is a standard SSD, you need to configure the client_data file by set instance_disk_cloud_ssd to true.
  3. Configure the user_config.json file. For more information, see Full migration.

  4. Run the Cloud Migration tool until the migration is completed.

What to do next

Start the target ECS instance to verify that the system runs normally.