Server Migration Center (SMC) allows you to migrate Elastic Compute Service (ECS) instances across zones in a region and change the types of the ECS instances at the same time.
Prerequisites
The cross-zone migration feature is commercialized, but the instance type change feature is available only to specific users. If you want to try the instance type change feature, submit a ticket. Your account will be added to the whitelist.
The information about one or more migration sources is imported. You can import the information about a migration source by using one of the following methods:
The instances are not preemptible instances and use the subscription or pay-as-you-go billing method.
The instance families to which the instances belong support instance type changes. For information about instance families that do not support instance type changes, see the Limits section of this topic.
Snapshots are created for the disks of the instances. For more information, see Create a snapshot for a disk.
The instances reside in virtual private clouds (VPCs). If you want to change the instance type of an ECS instance that resides in the classic network, you must migrate the instance from the classic network to a VPC. For more information, see Migrate ECS instances from the classic network to a VPC.
Applications deployed on the instances do not rely on the current private IP addresses of the instances. If you select a new vSwitch when you change the instance type of an instance across zones, the system assigns a new private IP address to the instance.
The following items are not configured for the instances: IPv6 addresses, high-availability virtual IP addresses (HAVIPs), elastic network interfaces (ENIs), reverse proxies, and route tables. Alibaba Cloud Global Accelerator is disabled for the instances.
Scenarios
The available instance types of ECS instances in the current zone cannot meet your business requirements. You want to change the instance types of the instances to a specific instance type in a different zone within the same region.
You want to migrate ECS instances to a different zone within the same region as your business requirements change.
Billing
Feature | Billing rule |
Across-zone server migration | Migration of servers across zones is free of charge. |
Across-zone instance type change | You are charged for changing instance types across zones based on the following billing rules:
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Limits
- The following instance families do not support cross-zone instance type changes:
- Heterogeneous computing instance families
- ECS Bare Metal Instance families
- Super Computing Cluster (SCC) instance families
- Instance families based on the x86 architecture:
- Big data instance families
- Instance families with local SSDs
- Security-enhanced instance families
- If you want to change the instance type of an instance to a new instance type, the new instance type must belong to the same instance family as the original one.
Usage notes
If security software such as Safedog, Huweishen, or Yunsuo is installed on the ECS instances whose instance types you want to change, disable the software before you change instance types across zones. Otherwise, virtualization drivers may fail to be installed and the instances cannot be started. You can enable the software after you change the instance types across zones.
Make sure that the system disks of the ECS instances have more than 500 MiB of available space. Otherwise, virtualization drivers may fail to be installed and the instances cannot be started.
During cross-zone instance type changes, do not stop, restart, or release the ECS instances manually or by using O&M scripts.
You can refund an instance up to three times. An instance type downgrade may result in a refund, which consumes the refund quota.
Migration impacts
Item | Description |
Amount of time required to migrate an instance | It takes about 15 minutes from when the instance is stopped until when it is migrated and started. Note After the computing and network resources of the instance are migrated, the instance is started. After the instance is started, the system continues to migrate disk data of the instance. Typically, it takes about 4 hours to migrate 100 GiB of disk data. During the migration, the I/O performance of disks degrades and snapshot- and disk-related features are not supported. |
Instance state | During migration, the instance is stopped and then started again. We recommend that you schedule to migrate your instance during off-peak hours. |
Software authorization code | After an instance is migrated, its software authorization codes may change. |
IP address |
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Fee |
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Other |
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Procedure
Log on to the SMC console.
In the left-side navigation pane, click Migration Sources.
On the Migration Sources page, click Import Migration source.
On the ECS Instance tab, find the migration source for which you want to create a migration job and click Create Migration Job in the Actions column.
If you want to change the instance types of multiple instances at a time, select the source ECS instances and click Create Migration Job below the migration source list.
In the Create Migration Job dialog box, configure the parameters.
The following table describes the parameters.
Parameter
Description
Migration Job Type
The type of the migration job. Select Cross-zone Migration.
Billing Method
If you change the instance type of only one instance, the current billing method of the instance is displayed by default. Example: Subscription.
If you change the instance types of multiple instances at a time, select Subscription or Pay-as-you-go based on your business requirements.
ImportantThis parameter takes effect for all the selected instances at a time only if the current billing methods of the instances are the same.
Region
If you change the instance type of only one instance, the current region in which the instance resides is displayed by default. Example: China (Hangzhou).
If you change the instance types of multiple instances at a time, select a region based on your business requirements.
ImportantThis parameter takes effect for all the selected instances at a time only if the instances reside in the same region.
Configuration-changed Instances to Be Migrated
By default, the source ECS instances are displayed.
Click Next.
In the Change Instance Type Across Zones dialog box, configure the parameters.
The following table describes the parameters.
Parameter
Description
Migration Job Type
The type of the migration job. By default, ECS Instance Migration is displayed.
Region
The current region of the instances. By default, the region in which the ECS instances reside is displayed. Example: China (Hangzhou).
Preferred Destination Zone
The zone to which you want to migrate the instances.
Preferred Network Settings
The destination vSwitch. After the instances are migrated, new private IP addresses that belong to the CIDR block of the vSwitch are randomly assigned to the instances.
ImportantAfter the instance types of the instances are changed across zones, the original private IP addresses of the instances cannot be retained. Make sure that no applications deployed on the instances rely on the original private IP addresses.
Instance Type
Specify whether to change the instance types based on your business requirements.
Use Current Instance Type: Do not change the instance types.
Change Instance Type: Change the instance types. Only specific instance families support instance type changes. For more information, see Instance families that support instance type changes.
ImportantYou can change an instance type only into another type within the same instance family.
Preferred New Instance Type
The destination instance type.
NoteThis parameter is displayed only if you select Change Instance Type as Instance Type.
Configuration-changed Instances to Be Migrated
Specify whether to preview the information about the instances, such as the instance IDs or names, zones, current type, VPC, destination zone, destination type, and destination vSwitch.
NoteYou can reselect the destination zone and destination vSwitch. If you select Change Instance Type as Instance Type, you can also reselect the destination instance type.
Notes
Select ECS Terms of Service and I have backed up data.
Click OK. In the dialog box that appears, click Pay to complete the payment as prompted.
NoteWhen you migrate servers across zones, the value of the Estimated Cost parameter indicates the estimated fees for the instances after migration.
Return to the SMC console to view the cross-zone migration progress.
Log on to the SMC console.
In the left-side navigation pane, click Migration Jobs.
Click the Cross-zone Migration tab and view the migration progress in the Status column.
The change of instance types takes a period of time.
If the state of the migration job changes to Completed, the cross-zone migration is complete.
If the state of the migration job changes to InError, the cross-zone migration failed. You can click View Logs in the Actions column to troubleshoot issues and rerun the migration job.