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    Server Migration Center:Migrate a server to an ECS instance

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    Server Migration Center:Migrate a server to an ECS instance

    Last Updated:Jun 05, 2025

    Server Migration Center (SMC) allows you to migrate servers from on-premises data centers, local virtual machines (VMware, VirtualBox, Xen, KVM, and Hyper-V), and other cloud service providers (Amazon Web Services, Microsoft Azure, Google Cloud Platform, Tencent Cloud, UCloud, China Telecom Cloud, and QingCloud) to Elastic Compute Service (ECS) instances on Alibaba Cloud securely and efficiently. SMC simplifies the migration process and significantly reduces the technical barriers and risks associated with server migration.

    Migration scenarios

    Important

    Server Migration Center (SMC) will upgrade the SMC client version to 2.8.6 on November 30, 2025. SMC will no longer support migrating Windows servers to Alibaba Cloud regions outside the Chinese mainland. For more information about the changes and impacts, see [Product Change] Announcement on SMC no longer supporting Windows server migration to Alibaba Cloud regions outside the Chinese mainland.

    • (Recommended) Migrate a server to an ECS custom image.

      If you have not purchased an ECS instance, you can migrate your server to an ECS custom image and then manually create an ECS instance from the custom image.

    • Migrate a server to a purchased ECS instance.

      If you have purchased an ECS instance and the storage, operating system, and other configurations of the purchased ECS instance are compatible with those of the source server, you can migrate the source server to the purchased ECS instance.

      Warning

      After the migration, the original data in the destination ECS instance will be cleared (the data on the source server will not be affected). If the destination ECS instance contains important data, we recommend that you do not migrate data from a simple application server to the destination ECS instance.

    Migration impacts

    Before you migrate data, you must understand the impacts caused by migration. The following table describes the impacts.

    Item

    The description

    Data directory

    During migration, SMC can automatically generate a target disk partition structure that is as consistent as possible with the disk partition structure of the source server. You can adjust the target disk partition structure as needed, including the partition size and position order, transmission method, and whether to enable LVM.

    By default, all disks of the server are migrated:

    • If no mount points exist on a data disk, the data disk is not migrated.

    • If you do not need to migrate certain partition directories, you can choose not to migrate them when adjusting the disk partition structure.

    For more information, see Adjust the disk partition structure as needed.

    Intermediate instance

    Do not interfere with the intermediate instance.

    To avoid migration failure, do not stop, start, restart, release the intermediate instance, or change the billing method of the intermediate instance during migration. After the migration is complete, SMC automatically releases the intermediate instance.

    Note

    • Each time a migration is performed, SMC creates a pay-as-you-go temporary intermediate instance named No_Delete_SMC_Transition_Instance in your Alibaba Cloud destination account to assist with the migration. For information about the default instance types, see What are the specifications of an intermediate instance?

    • If you choose to migrate to a destination instance, the destination instance is the intermediate instance, and this instance is not automatically released.

    For more information, see Migration principles.

    IP address

    After the migration, the IP address will change, which may cause service interruption. We recommend that you perform the migration during off-peak hours. If your business involves IP address configuration, you need to modify domain name resolution, ICP filing, and other settings after the migration.

    Underlying hardware

    After the migration, the underlying hardware may change, and the application licenses that are associated with the underlying hardware may become invalid. Perform checks based on your business requirements.

    Peripheral impacts on web applications after server migration

    After a server is migrated to an Alibaba Cloud ECS instance, the network topology, computing and storage resources, application security settings, costs, monitoring, compatibility, network latency and bandwidth, backup and recovery, and O&M processes will change. You also need to pay attention to the following aspects:

    Item

    The description

    Network connectivity

    After server migration, the ECS instance will use a new virtual private cloud (VPC), and its network location and other configurations will change with the migration of the VPC. This ECS instance cannot directly communicate with the original network or other ECS instances in the VPC. If you need to enable communication across accounts and VPCs, see VPC peering.

    Security group

    After server migration, the ECS instance will use new security group rules to control inbound and outbound traffic, and changes in access rules may affect normal business access. If there are no corresponding security group rules in the security group of the destination account, you can quickly add security group rules by exporting the security group rules associated with the original ECS instance and importing them to the destination security group. For more information, see Import and export security group rules.

    SSL Certificate

    If your website uses HTTPS services, you need to apply for and install an SSL certificate. You can apply for a free SSL certificate through Alibaba Cloud and deploy the SSL certificate to the ECS instance. For more information, see Purchase and deploy an SSL certificate to an ECS instance.

    Data migration

    If you need to migrate data from other servers to Alibaba Cloud, you can use methods such as FTP, SCP, or manual backup to OSS for data migration. For more information, see Transfer files to an ECS instance and Use ossutil to transfer data to an ECS instance.

    Other Configuration

    Database connections, APIs, Server Load Balancer (SLB), etc., ensure that they point to the new domain name and ECS IP address.

    Preparations

    • You have completed the preparations before server migration. For more information, see Preparations before migration.

    • You have understood the SMC client, migration principles, migration billing, migration process, and feedback channels. For more information, see Migration guide.

    • To avoid data loss, we recommend that you back up important data to an image, snapshot, or storage device other than the instance.

    • If you need to migrate servers across international regions, the migration speed may be slow due to the unstable public network environment. For more information, see Evaluate migration time and test transmission speed. We recommend that you connect the source server and the VPC on Alibaba Cloud through a VPN gateway, Express Connect, Express Connect circuit, or Smart Access Gateway, and migrate through a private network. For more information, see Connect an on-premises data center to a VPC.

    • If you can directly access a VPC in an Alibaba Cloud region from your on-premises data center, virtual machine environment, or cloud host, we recommend that you use the private network transmission migration solution of SMC. Migration through SMC's private network transmission is faster and more stable than through the public network, which can improve migration efficiency. For more information, see Migrate through a private network.

    • If you need to migrate the source server to a purchased Alibaba Cloud ECS instance:

      • Important data on the destination ECS instance is backed up to an image, snapshot, or storage device other than the destination instance.

      • If the source server runs a Linux operating system, the destination instance must run a Linux distribution. If the source server runs a Windows operating system, the destination instance must run a Windows operating system.

      • The number of data disks attached to the destination ECS instance is greater than or equal to the number of data disks attached to the migration source. If the number of data disks attached to the destination instance does not meet the requirements, you must attach more data disks. For more information about how to attach data disks, see Attach a data disk.

      • The capacity of the system disk and data disks attached to the destination ECS instance is greater than or equal to the capacity of the system disk and data disks attached to the migration source. If you want to scale down the system disk and data disks attached to the migration source, make sure that the capacity of the system disk and data disks attached to the destination ECS instance is greater than or equal to the capacity actually consumed by the data on the system disk and data disks attached to the migration source. If the capacity of the disks attached to the destination instance does not meet the requirements, you must scale up the disks. For more information about how to scale up disks, see Disk resizing overview.

    Migration procedure

    Step 1: Import the information of the migration source

    A migration source refers to the server that you want to migrate, such as an on-premises server, a virtual machine, a cloud host on another cloud platform, or another type of server. SMC supports multiple methods to import the information of migration sources. You can select an appropriate method based on your actual needs. For more information, see How do I choose a method to import the information of a migration source?

    Import the information of a migration source by using a command (recommended)

    Important

    • The source server must have access to the Internet. If the source server has firewall restrictions, see What are the service domains of SMC? to obtain the SMC domain names and ports, and add them to the firewall whitelist.

    • If your source server cannot access the Internet or you want to improve migration efficiency through private network transmission, import the information of the migration source by using the SMC client.

    1. Visit SMC console - Server Migration.

    2. On the Server Migration page, click Import Migration source.

    3. Configure the parameters as prompted and copy the activation code command. The following table describes the parameters.

      Parameter

      Description

      Workgroup (optional)

      Applies to batch migration to ECS images. Skip this parameter for single server migration.

      You can add multiple migration sources to the same workgroup for management. Migration sources associated with a workgroup must enable automatic incremental synchronization during migration. For more information about batch server migration, see Batch server migration.

      If you have not created a workgroup, click Create a New Workgroup.

      Migration Source Type

      Select Physical Machine/Virtual Machine/Server On Other Cloud Platform.

      Import Method

      Select Command Line Import: Generate an activation code script command as needed, and execute it on the source server with one click to import the migration source.

      Migration Source Quota

      The number of migration sources whose information can be imported by using the activation code. Valid values: 1 to 1000. Default value: 200.

      Validity Period

      The validity period of the activation code. Valid values: 1 to 90 days. Default value: 90 days.

      Activation Code

      After the activation code is generated, copy the command. Perform the following steps:

      1. Click Generate.

      2. Based on the operating system of the source server, click the Linux Shell or Windows Powershell tab.

      3. Click Copy to copy the activation code command.

    4. Log on to the source server and run the copied command with administrator privileges to import the information of the migration source.

      Linux source server

      1. Log on to the Linux source server.

      2. Run the copied command with administrator privileges to import the information of the migration source.

        image.png

        After the command is executed, a message similar to Import Source Server [s-bp18x8751kgz2oyh****] Successfully! appears, indicating that the information of the migration source is imported.

      Windows source server

      1. Log on to the Windows source server.

      2. Open Windows PowerShell as an administrator.

      3. Paste the copied command and execute it to import the information of the migration source.

        image.png

        After the command is executed, a message similar to Import Source Server [s-bp19rlidl3mwuptc****] Successfully! appears, indicating that the information of the migration source is imported.

        If the command execution fails, see How do I resolve the issue when the command fails to import the information of a Windows migration source?

    5. On the Server Migration page of the SMC console, view the status of the migration source in the Migration Status column.

      • If the migration source is in the Online state, the information of the migration source is imported.

      • If the migration source is in another state, the information of the migration source fails to be imported. Resolve the issue by using the following solutions and then import the information of the migration source again:

        • Troubleshoot the issue based on the message displayed in the SMC console or the log file in the directory where the SMC client is installed. The default installation directories of the SMC client are as follows:

          • Windows source server: The default installation directory is C:\smc.

          • Linux source server: The default installation directory is /smc.

        • For more information about common issues and solutions, see SMC FAQ and Troubleshooting.

    Automatically import the information of a migration source in the console

    Important

    • This method supports only importing the information of Alibaba Cloud ECS instances.

    • The source server must be in the Running state, and Cloud Assistant must be available. For more information, see View the Cloud Assistant status and handle exceptions.

    • If you use a RAM user to import the information of a migration source, you must grant the following permissions to the RAM user:

      • You must grant the RAM user the AliyunECSReadOnlyAccess permission to access ECS in read-only mode. For more information, see Grant permissions to a RAM user.

      • You must grant the RAM user the Cloud Assistant management permission AliyunECSAssistantFullAccess. For more information, see Grant permissions to a RAM user.

    1. Visit SMC console - Server Migration.

    2. On the Server Migration page, click Import Migration source.

    3. Configure the parameters based on the migration source type.

      Parameter

      Description

      Workgroup (optional)

      Applies to batch migration to ECS images. Skip this parameter for single server migration.

      You can add multiple migration sources to the same workgroup for management. Migration sources associated with a workgroup must enable automatic incremental synchronization during migration. For more information about batch server migration, see Batch server migration.

      If you have not created a workgroup, click Create a New Workgroup.

      Migration Source Type

      Select Alibaba Cloud ECS Instance.

      Import Method

      Select Console Import: Authorize Server Migration Center to remotely connect to the source server in the console to automatically import the information of the migration source. During the import process, the Cloud Assistant feature is automatically called. Do not exit the process.

      Region

      The region in which the migration source resides.

      Instance

      The ECS instance whose information you want to import. You can select multiple ECS instances to import the information about the ECS instances at a time.

      You can search for the ECS instance to be migrated by instance ID/name and IP address.

      Tag (optional)

      Bind tag key-value pairs to the migration task for easy query and management of migration tasks. For more information, see Use tags to manage migration sources and migration tasks and Implement fine-grained permission management by using tags.

      Note

      You can bind up to 20 tags to a migration task.

      Resource Group (optional)

      If you need to manage migration resources by department, project, or other dimensions, you can create resource groups to achieve this.

    4. After you configure the parameters, click Import.

      SMC automatically starts Cloud Assistant to perform the import. It takes about 3 to 10 minutes to import the information of the migration source. Please wait patiently.

    5. On the Server Migration page of the SMC console, view the status of the migration source in the Migration Status column.

      • If the migration source is in the Online state, the information of the migration source is imported.

      • If the migration source is in another state, the information of the migration source fails to be imported. Resolve the issue by using the following solutions and then import the information of the migration source again:

        • Troubleshoot the issue based on the message displayed in the SMC console or the log file in the directory where the SMC client is installed. The default installation directories of the SMC client are as follows:

          • Windows source server: The default installation directory is C:\smc.

          • Linux source server: The default installation directory is /smc.

        • For more information about common issues and solutions, see SMC FAQ and Troubleshooting.

    Import the information of a migration source by using the SMC client

    For more information about the SMC client, see SMC client user guide.

    Important

    • Client import requires the source server to run the client, and the public network access mode is enabled by default. If the source server has firewall restrictions, see What are the service domains of SMC? to obtain the SMC domain names and ports, and add them to the firewall whitelist.

    • If your source server cannot access the Internet or you want to improve migration efficiency through private network transmission, see Migrate through a private network to set up private network transmission.

    1. Visit SMC console - Server Migration.

    2. On the Server Migration page, click Import Migration source.

    3. On the Import Migration Source page, configure the parameters described in the following table.

      Parameter

      Description

      Migration Source Type

      Select Physical Machine/Virtual Machine/Server On Other Cloud Platform.

      Import Method

      Select Client Import: Manually download and install the SMC client on the source server.

      Import Instructions

      In the Import Instructions section, download, install, and activate the corresponding SMC client based on the operating system (Linux and Windows) and bit (32-bit and 64-bit) of the source server.

      Click Generate Activation Code and copy the activation code information. You need to enter the activation code when you install the client.

    4. Import the information of the migration source.

      Select the corresponding operation based on the operating system of the source server:

      Important

      Do not close the SMC client during migration until the migration is complete. Otherwise, the migration source will be disconnected from the SMC console and the migration fails.

      Import the information of a Windows migration source

      1. Use a third-party remote connection tool that supports file transfer to upload the SMC client to the Windows source server. For example, WinSCP.

      2. On the Windows source server, use the built-in decompression tool or a decompression tool that you have installed to decompress the SMC client package.

      3. Run the SMC client in the folder that is compatible with the version of your migration source system.

        • GUI version: Double-click the go2aliyun_gui.exe application.

        • Command line version: Double-click the go2aliyun_client.exe application.

        Note

        When the program runs, you are prompted for administrator privileges. Click OK.

      4. Obtain the activation code or AccessKey pair.

        • (Recommended) Obtain the activation code: In the Import Instructions section of the SMC console, click Generate Activation Code and copy the activation code information.

        • Obtain the AccessKey pair: The AccessKey pair of an Alibaba Cloud account consists of an AccessKey ID and an AccessKey secret. If you have not created an AccessKey pair, create one first. For more information, see Create an AccessKey pair.

      5. Enter the activation code or AccessKey pair as prompted.

        • GUI version: In the Token Id/AK and Token Code/SK text boxes, enter the activation code or AccessKey pair, and then click Run. For more information, see SMC client user guide.

        • Command line version: Enter the values of the activation code access_access_token_id and access_token_code, and press Enter.

        When a message similar to Import Source Server [s-bp18x8751kgz2oyh****] Successfully! appears, the information of the migration source is imported.

      Import the information of a Linux migration source

      1. Use a third-party remote connection tool that supports file transfer to upload the SMC client package to the Linux source server. For example, WinSCP.

      2. Remotely connect to the Linux source server and decompress the SMC client package.

        In this example, Linux 64-bit General Version is decompressed. If you use another version of the SMC client, replace the package name in the command with the actual name of the downloaded SMC client.

        tar -zxvf go2aliyun_client.tar.gz
        Note

        Linux 64-bit ARM Version supports the g6r general-purpose instance family and the c6r compute-optimized instance family. For more information about instance types, see Enterprise-level ARM computing instance family groups.

      3. (Optional) If you do not need to migrate some files or directories, you can exclude them from migration. For more information, see How do I filter and exclude files or directories from migration?

        Important

        If you enable the block replication feature, you cannot exclude files or directories from migration.

      4. Obtain the activation code or AccessKey pair.

        • (Recommended) Obtain the activation code: In the Import Instructions section of the SMC console, click Generate Activation Code and copy the activation code information.

        • Obtain the AccessKey pair: The AccessKey pair of an Alibaba Cloud account consists of an AccessKey ID and an AccessKey secret. If you have not created an AccessKey pair, create one first. For more information, see Create an AccessKey pair.

      5. In the SMC client folder, run the following commands to run the SMC client.

        cd go2aliyun_client_linux_x86_64
sudo chmod +x go2aliyun_client
sudo ./go2aliyun_client

      6. Enter the activation code or AccessKey pair as prompted. This example uses the activation code:adad

        After you enter the activation code or AccessKey pair, the following prompts may appear:

        • If no snapshot dependency is installed on your source server, the following prompt appears, as shown in the following figure. Decide whether to install one based on whether you need to enable block replication.

          • If you want to enable block replication when you create a migration task, enter yes to automatically install a snapshot dependency.

          • If you do not want to enable block replication when you create a migration task, enter no.

          Important

          If the snapshot dependency fails to be installed, do not enable block replication when you create a migration task. Otherwise, the migration fails.

          123

        • Most mainstream migration source systems have rsync installed by default. If rsync is not installed, the SMC client prompts you to enter yes to automatically install rsync, as shown in the following figure.安装rsync

        • If SELinux is enabled on the source ECS instance, you are prompted to disable SELinux. Enter yes to automatically disable SELinux, as shown in the following figure.关闭SELinux

        When a message similar to Import Source Server [s-bp11npxndknsycqj****] Successfully! appears, the information of the migration source is imported.

        Note

        If the information of the migration source fails to be imported, you can resolve the issue based on the returned message, and then run the following commands to exit the background program and import the information of the migration source again. For more information about common issues and solutions, see SMC FAQ and Troubleshooting.

        sudo ./go2aliyun_client --abort
sudo ./go2aliyun_client

    5. On the Server Migration page of the SMC console, view the status of the migration source in the Migration Status column.

      • If the migration source is in the Online state, the information of the migration source is imported.

      • If the migration source is in another state, the information of the migration source fails to be imported. Resolve the issue by using the following solutions and then import the information of the migration source again:

        • Troubleshoot the issue based on the message displayed in the SMC console or the log file in the directory where the SMC client is installed. The default installation directories of the SMC client are as follows:

          • Windows source server: The default installation directory is C:\smc.

          • Linux source server: The default installation directory is /smc.

        • For more information about common issues and solutions, see SMC FAQ and Troubleshooting.

    Step 2: Configure migration settings

    1. Find the migration source that you want to manage and click Start Migration in the Actions column.

    2. Configure the parameters and click Start Migration.

      1. Configure the basic parameters described in the following table.

        Parameter

        Description

        Example

        Task Name

        The name of the migration job.

        Server Migration

        Task Description

        The description of the migration job.

        test

        Destination Type (required)

        You can select the corresponding destination type based on your actual migration scenario:

        ECS image

        Convert the existing source server into an ECS custom image, and then use the custom image to create a new ECS instance to implement migration.

        Fields:

        • Destination Region: The region to which your source server is to be migrated. This parameter is required. For more information about regions, see Regions and zones.

        • Image Name: The name of the Alibaba Cloud custom image that SMC generates for the migration source.

        ECS instance

        Migrate the source server directly to a purchased ECS instance. The storage, operating system, and other configurations of the source server and the purchased ECS instance must be compatible.

        Important

        When you migrate to a destination instance, the operating system of the destination instance is replaced, and the automatic snapshots of the system disk are cleared and cannot be restored. If you need to retain automatic snapshots for future needs or data security considerations, you can manually cancel the automatic snapshot release with the disk before migration. For more information, see Configure whether to release automatic snapshots along with a disk.

        Fields:

        • Destination Region: The region to which your source server is to be migrated. This parameter is required. For more information about regions, see Regions and zones.

        • Destination Instance: Select an ECS instance as the destination instance.

        ECS Image

        Migration Test

        The migration test feature helps you understand the feasibility and risks of a migration job before the migration job starts and provides solutions to identified issues. You can also obtain information such as the amount of data to be migrated, migration speed, and total duration of the migration. This helps reduce the issues and losses that may occur during the actual migration. During the test, you are charged for pay-as-you-go resources. By default, Migration Test is enabled.

        Warning

        If the target type is Elastic Compute Service Instance, snapshots will be created for all disks of the target ECS instance during the migration drill. If the drill is abnormal or the execution method is Drill Only, the snapshots will be automatically rolled back after the migration drill is completed. The target ECS instance will not be active during the migration drill, and data will be lost during this period. Please ensure that there is no important data in the target ECS instance.

        For more information, see Configure migration test.

        Default

        Execution Method

        Select an execution method based on whether Migration Test is enabled:

        If Migration Test is enabled

        • Test Only: Only a migration test task is created. After the migration test is complete, if you need to migrate the server, you must manually start the server migration task.

        • Test And Migrate: After the migration test is complete, if no test item is in the Critical state, the system automatically starts the server migration task. Test And Migrate is selected by default.

        If Migration Test is disabled

        • Migrate Now: The migration starts immediately after the migration task is created. Migrate Now is selected by default.

        • Schedule Migration: After the migration task is created, the migration task automatically starts at the specified time.

          Note

          The earliest scheduled execution time can be set to 10 minutes after the current time.

        • Create Only: Only a migration task is created. Later, you need to click Start Task in the Actions column to manually start the migration task.

        Default

        Automatic Incremental Synchronization

        Specifies whether to automatically synchronize incremental data from the source server to Alibaba Cloud. By default, automatic incremental synchronization is disabled.

        • If you turn on this switch, you need to configure the following items:

          • Synchronization Interval: The time interval at which the incremental migration task is automatically executed periodically.

          • Maximum Number Of Images To Retain: The maximum number of images that the incremental migration task retains by default.

          The migration task is automatically executed periodically to synchronize incremental data to Alibaba Cloud. For more information about the best practices for incremental migration, see Incremental server migration.

        • If you turn off this switch, the migration task is executed only once.

        Default

        Enable Migration Template

        This parameter appears only when Destination Type is set to ECS Image.

        Migration templates are used to preset parameters for migration tasks, and the template parameters are automatically filled in when migration starts. For more information about how to set migration templates, see Set migration templates.

        Default

      2. Adjust the disk partition structure as needed. The following table describes the parameters.

        Parameter

        Description

        Example

        Adjust Disk Partition Structure

        Choose whether to enable the adjustment of the disk partition structure based on your needs. Only SMC client version 2.8.0 and later support this feature. For more information about the SMC client, see SMC client user guide.

        • Not enabled: The target disk partition structure is the same as that of the migration source by default.

        • Enabled: You can adjust the target disk partition structure, including the partition size and position order, transmission method, and whether to enable LVM.

          The following table describes the parameters of the disk partition structure:

          Configure disks

          • System Disk: The size of the system disk of the destination Alibaba Cloud server. Unit: GiB. Valid values for the system disk size: 20 to 2048.

            The size of the destination system disk must be greater than the amount of data in the source system disk. For example, if the total size of the source system disk is 400 GiB but the size of data stored in this disk is only 100 GiB, you must set this parameter to a value greater than 100 GiB.

            Note

            The default value is the size of the source system disk. If you do not need to scale down the system disk, we recommend that you do not set this parameter to a value smaller than the default value.

          • Data Disk <N>: The size of a data disk on the destination Alibaba Cloud server. Unit: GiB. Valid values for the data disk size: 1 to 32768.

            • The variable <N> indicates the sequence number of the data disk. If you migrate to a destination instance, N is the ID of the data disk.

            • The size of the destination data disk must be greater than the amount of data in the source data disk. For example, if the total size of the source data disk is 500 GiB but the size of data stored in this disk is only 100 GiB, you must set this parameter to a value greater than 100 GiB.

            • If no mount points exist on a Data Disk or all mount points are set not to be migrated, the data disk is not migrated.

          • LVM: Logical Volume Manager (LVM) is a mechanism for managing disk partitions in Linux systems. LVM is more flexible than ordinary disk partitions and allows you to dynamically adjust disk space.

            You can choose whether to enable LVM based on your needs. After LVM is enabled, the system automatically rebuilds the disk with the LVM structure on the destination.

            Examples:

            For each destination disk with LVM enabled, the system creates one physical volume (PV) and its corresponding volume group (VG), and creates logical volumes (LVMs) on the volume group corresponding to the number of mount points. The volume group name is vgX by default (X is the sequence number of the disk), and the logical volume name is lvX by default (X is the sequence number of the logical volume), as shown in the following example:

            image

            Important

            LVM is not supported in the following scenarios:

            • When the migration source is a Windows system, LVM is not supported.

            • When the system disk has no boot partition, LVM is not supported.

            After LVM is enabled, this feature does not take effect in the following scenarios:

            • The migration source does not support lvm2 or the lvm2 software package is not installed.

            • The migration source is a Debian system with a kernel version of 3.x or earlier, and a disk with the XFS file system is mounted.

          Configure mount points

          • Migrate: You can choose whether to migrate the mount point based on your business needs.

          • Enable Block Replication: Block replication can effectively improve the stability of migration transmission speed and ensure consistency with the source partition structure, but the partition size cannot be modified. SMC determines whether to support enabling block replication based on the disk partition status of the migration source.

            • If the migration source does not support enabling Block Replication for partitions, this switch cannot be turned on, and the default file replication is used. The partition size can be modified.

            • If the migration source supports enabling Block Replication for partitions, block replication is enabled by default to implement disk migration at the partition level.

            Note

            • When the migration source is a Windows operating system, the block replication feature is enabled by default and cannot be disabled.

            • If LVM is enabled for the disk and the partition size is not a multiple of 4 MiB, block replication does not take effect, and the data transmission method uses file replication.

          • Set Partition Size: When block replication is not enabled, you can set the partition size as needed, but the sum of partition sizes cannot exceed the size of the disk to which they belong.

          Note

          If the sizes of the disks of the destination instance do not match those of the migration source disks, the task cannot be created. In this case, the system automatically adjusts the mount point positions to meet the disk size requirements. If the requirements still cannot be met after the mount points are adjusted, handle the issue according to the prompt information on the interface.

          You can also manually drag the mount point positions to meet the disk size requirements. However, partition types that are boot partitions or system partitions do not support dragging. Perform the following steps:

          1. Hover your mouse over the image icon in front of the mount point.

          2. Use the mouse to drag the mount point to another disk.

        Default

      3. (Optional) If you need to set the network mode, modify the private IP address, limit the transmission speed, or configure other parameters, click Advanced Configuration and configure the advanced parameters described in the following table.

        Parameter

        Description

        Example

        Network Mode

        Select the network used to transfer migration data to the intermediate instance. By default, the public network is used for transmission. The intermediate instance is created in the selected virtual private cloud (VPC) and vSwitch. Therefore, a public IP address is assigned to the intermediate instance.

        Public Network (default)

        Migration data is transmitted to the intermediate instance over the public network. To use this mode, the source server must be able to access the public network. Choose whether to specify a VPC and a vSwitch based on your actual needs.

        • Specify a VPC and a vSwitch: The migration task creates an intermediate instance in the specified VPC and vSwitch.

        • Do not specify a VPC or a vSwitch: The migration task creates an intermediate instance in a VPC and a vSwitch that are automatically created by the system.

        Private network

        Migration data is transmitted to the intermediate instance over the VPC internal network. To use this mode, you must connect the source server to the Alibaba Cloud VPC and specify a VPC and a vSwitch.

        Note

        If you can directly access a VPC in an Alibaba Cloud region from your on-premises data center, virtual machine environment, or cloud host, we recommend that you use this method for migration. Migration through the internal network is faster and more stable than migration through the public network, which improves migration efficiency. You can connect the source server to the VPC on the cloud through a VPN gateway, Express Connect circuit, or Smart Access Gateway. For more information, see Connect an on-premises data center to a VPC.

        Default

        IPv4 Private Address

        If you need to change the private IP address of the destination instance, you can manually specify a private IP address. This parameter appears only when Destination Type is set to ECS Instance.

        • Keep Unchanged: By default, the migration IP address of the destination instance remains unchanged.

        • Manually Specify: You can enter an address within the available IP address range of the vSwitch to which the destination instance belongs. When the IP address of the migration source is within the CIDR block of the vSwitch, you can modify the IP address of the destination instance to the IP address of the migration source.

          • When the CIDR block of the destination instance is the same as that of the migration source: Directly enter the private IP address of the migration source.

          • When the CIDR block of the destination instance is different from that of the migration source: You need to first change the VPC of the destination instance to make the CIDR block of the destination instance the same as that of the migration source, and then enter the private IP address of the migration source.

        Transmission Speed Limit

        The transmission speed limit restricts the actual network transmission speed. Unit: Mbit/s. If the Compression Ratio is set to a value greater than 0, the actual network transmission speed (the transmission speed of compressed data) is less than the speed displayed in Migration Status.

        Default

        Compression Ratio

        The level of data compression during migration. Set the compression ratio based on your actual needs.

        • In bandwidth-limited environments, a high compression ratio can improve data transmission speed.

        • When the bandwidth is high, we recommend that you do not compress data during transmission to reduce the consumption of CPU resources of the migration source.

        Valid values: 0 to 10. Default value: 7. The value 0 indicates that data is not compressed.

        Default

        Checksum Verification

        This feature is disabled by default. After it is enabled, it can enhance data consistency verification, but may reduce the transmission speed.

        Default

        Enable SSL Encrypted Transmission

        This feature is enabled by default. Using SSL encrypted transmission for migration data can improve data security and ensure data integrity.

        Default

        License Type

        The license type.

        • Alibaba Cloud (default): Currently, only Microsoft Windows Server licenses are provided. After migration, when you use the image to create an ECS instance in the China (Hong Kong) region or regions outside China, you are charged for the image license, and the license is automatically activated. The specific fee is subject to the information displayed when you create the instance.

        • BYOL: Bring Your Own License (BYOL) for cloud migration currently includes Microsoft, Red Hat Enterprise Linux, and SUSE Linux Enterprise Server. After migration, when you use the image to create an ECS instance, you are not charged for the image license. You need to use your own license for activation.

          Note

          If you have created an ECS instance, Alibaba Cloud supports purchasing software licenses such as Red Hat Enterprise Linux and SUSE Linux Enterprise Server for the specified ECS instance. For more information, see Purchase a software license for an ECS instance (invitational preview).

        Default

        Image Check

        The image check feature checks whether an image is valid and whether the image can be used to create full-featured Elastic Compute Service (ECS) instances. You can use the image check feature when you create server migration and VMware agentless migration tasks.

        Image check helps you quickly identify potential issues with images or instances after migration, provides solutions, and ensures that they meet Alibaba Cloud standards, improving the success rate of instance startup.

        For more information, see Configure image check.

        Default

        Tag

        Attach tag key-value pairs to migration tasks for easier query and management of migration tasks. For more information, see Use tags to manage migration sources and migration tasks and Implement fine-grained permission management by using tags.

        Note

        You can bind up to 20 tags to a migration task.

        Default

        Intermediate Instance Type

        You can select the intermediate instance type based on your actual needs. This parameter appears only when Destination Type is set to ECS Image.

        • Automatically Select Intermediate Instance Type: The system selects this instance type to create an intermediate instance. If the inventory of this instance type is insufficient, the migration task fails to be created.

        • Do not specify the parameter: SMC automatically creates an intermediate instance.

        Important

        To avoid migration errors, do not stop, start, restart, or release the intermediate instance during migration. After the migration is complete, the instance is automatically released.

        Default

    3. In the message that appears, read the migration notes and click Got It.

    4. On the Server Migration page, view the migration status.

      If you have enabled migration test, SMC will first perform a migration test, and then perform the migration operation after the test passes. The amount of time required for data transmission varies based on factors such as the data size of the migration source and the network bandwidth. Wait until the migration job is complete.

      image

      Note

      • Speed: The amount of migration data transmitted per second (the transmission speed of uncompressed data). If the Compression Ratio is set to a value greater than 0 when you create a migration task, the displayed speed is greater than the actual network transmission speed (the transmission speed of compressed data).

      • Remaining Synchronization Time: The remaining synchronization time calculated based on the current speed. Remaining synchronization time = (Total data volume - Transmitted data volume)/Speed.

      • If the transmission speed is too low to meet your plan, you can consider temporarily increasing the fixed bandwidth of the source server and the destination server. For more information, see Evaluate migration time and test transmission speed.

      Subscribe to migration error events, modify migration, and pause migration. The specific operations are as follows:

      • To avoid migration task errors that block the migration process, you can subscribe to SMC migration task error events in CloudMonitor to receive email notifications in a timely manner. For more information, see Subscribe to SMC migration task error event notifications.

      • When the migration task is in the Syncing state, you can also perform the following operations on the migration task based on your actual needs:

        • Edit the migration task: In the Actions column, click Modify Migration to modify parameters such as transmission speed limit, compression ratio, and checksum verification.

        • Pause the migration task: In the Actions column, click Pause Migration to pause the migration.

    5. (Optional) To view the migration details, follow these steps.

      View migration details

      In the Migration Source ID/Name column of the target migration source, click the migration source ID to view the migration details.

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    Verify the migration result

    • When the Migration Status is Completed, the migration is successful.

      • If the Destination Type of the migration is ECS Image:

        After the migration is successful, an Alibaba Cloud custom image is generated. You can use the mouse to scroll to the right in the bottom scroll bar, and click View Report in the Migration Deliverable column to view the image check result. For more information, see View the image check result.

        image

        Manually verify the migration result (recommended)

        In the Actions column, click Create Instance. The system redirects you to the ECS console Create ECS page and automatically selects the created custom image. For more information about how to create an ECS instance, see Create an ECS instance by using a custom image.

        image

        Automatically verify the migration result

        Note

        To use this feature, the Cloud Assistant plugin needs to be installed in the instance, and the instance system version must support it. For more information, see Install the Cloud Assistant agent.

        This feature uses the OOS template ACS-SMC-CreateAndVerifyInstance provided by Alibaba Cloud to automatically verify whether the image generated by the migration task can successfully create an ECS instance and start normally.

        1. In the Actions column, click Verify Migration Result.

          image

        2. In the dialog box that appears, learn about the verification process and click Verify Now.

          You can also click Customize Verification Script Parameters to manually configure parameters for verification.

        3. In the Verification Result column, view the verification result.

          • Verification Passed: The migration result has no exceptions. You can click Details to learn about the verification result.

          • Verification Not Completed: The migration result has exceptions. You can click View Reason to learn about the reason for the migration task error and troubleshoot the issue based on the reason.

          You can also click ... in the Actions column and click Go To OOS To View Historical Verification to obtain historical execution information of the OOS template.

      • If the Destination Type of the migration is ECS Instance, you can click View Destination Instance in the Actions column to go to the destination ECS instance page and view the destination ECS instance.

      After server migration, to ensure normal business operation, you need to perform the following operations:

    • If the migration test status is image.png, the migration test fails.

      You need to view the test report, fix the Critical test items, and then retry the migration test. For more information, see Configure migration test.

    • When the Migration Status is Error, the migration task has an error.

      In this case, you need to troubleshoot the issue and then retry:

      1. In the Actions column, click Troubleshoot and fix the issue based on the error code and error message. For more information, see SMC FAQ and Troubleshooting.

      2. After you fix the issue, click Retry Migration in the Actions column.

        The system continues the migration from where it left off.

        Important

        If the intermediate instance has been released, you need to migrate again. For more information, see What do I do if I accidentally release an intermediate instance?

    Clean up resources

    • Migration to an ECS image

      During migration, SMC creates a pay-as-you-go temporary intermediate instance named No_Delete_SMC_Transition_Instance in your Alibaba Cloud destination account to assist with the migration. You need to choose whether to manually clean up based on whether the migration is successful:

      • Migration successful: The intermediate instance is automatically released, and you do not need to manually clean up.

      • Migration error: The intermediate instance continues to exist with the migration task and incurs fees. You can choose one of the following methods to release the intermediate instance to avoid unnecessary charges:

        • If you have confirmed that you no longer need the migration task, click the migration source ID, and then click Clean Up Migration in the Actions column of the migration task to automatically clean up the intermediate instance by deleting the migration task.

        • Manually release the intermediate instance. For more information, see Release an instance.

    • Migration to a destination instance

      During migration, SMC creates a pay-as-you-go temporary intermediate disk named SMC_Temp_Disk on the destination instance to assist with the migration. You need to choose whether to manually clean up the intermediate disk based on whether the migration is successful:

      • Migration successful: The intermediate disk is automatically released, and you do not need to manually clean up.

      • Migration error: The intermediate disk continues to exist with the migration task and incurs fees. You can choose one of the following methods to release the intermediate disk to avoid unnecessary charges:

        • If you have confirmed that you no longer need the migration task, click the migration source ID, and then click Clean Up Migration in the Actions column of the migration task to automatically clean up the intermediate disk by deleting the migration task.

        • Manually release the intermediate instance. For more information, see Release a disk.

    References

    • If you need to migrate incremental data multiple times, after the first full migration is complete, you can perform multiple incremental migrations at custom time intervals to synchronize incremental data generated by the source server system to Alibaba Cloud, effectively reducing the system business downtime and final delivery time of the source server. For more information, see Incremental server migration.

    • For common issues and solutions, see FAQ and Troubleshooting.