All Products
Search

This Product

    Server Migration Center:Migrate incremental data from a VMware VM without an agent

    Document Center

    Server Migration Center:Migrate incremental data from a VMware VM without an agent

    Last Updated:Sep 07, 2023

    Server Migration Center (SMC) allows you to migrate incremental data from a VMware VM to Alibaba Cloud. You can specify the time interval between incremental migration tasks. Incremental migration reduces the VM downtime and the total duration of migration. This topic describes how to migrate incremental data from a VMware VM without an agent.

    Prerequisites

    The information about the VMware VM from which data is to be migrated is imported to the SMC console. For more information, see Import the information about a migration source by configuring a Server Migration Connector without agents.

    Step 1: Enable CBT

    In this topic, vCenter 6.7 is used. To migrate incremental data from a VMware VM, you must enable Change Block Tracking (CBT) for the VM. If you disable CBT, full data is migrated from the VMware VM. If CBT is already enabled, skip this step.

    Warning

    Before you enable CBT, make sure that no snapshots are generated for the VMware VM. Otherwise, the incremental data migrated by using CBT may be incorrect. If you delete the snapshots of the VMware VM when you enable CBT, execute the ./disk/migrate_configure file in the /root/smc directory, which is the home directory of the SMC client. This way, you can re-obtain the configuration information about the VMware VM.

    To enable CBT, make sure that the following conditions are met:

    • The version of the ESXi host is ESXi 4.0 or later.

    • The VM hardware version is 7 or later.

    • The I/O operations of the VMware VM must be performed in the ESXi storage.

    • The VMware VM supports Raw Device Mapping (RDM) and Virtual Machine File System (VMFS) in virtual compatibility mode and Network File System (NFS).

    • The VMware VM does not use independent persistent or nonpersistent disks to store data.

    1. Log on to vCenter Server.

    2. Right-click the VMware VM that has been powered off and select Edit Settings. ada

    3. On the Edit Settings page, click the VM Options tab. adad5

    4. Click Advanced and then EDIT CONFIGURATION... next to Configuration Parameters. ada5

    5. On the Configuration Parameters page, click ADD CONFIGURATION PARAMS and add the parameters described in the following table. adaaaaaa56

      Name

      Value

      Description

      ctkEnabled

      TRUE

      Specifies whether to use CTK files.

      scsi0:0.ctkEnabled

      TRUE

      Specifies whether to allow the use of CTK files for the hard disk whose small computer systems interface (SCSI) ID is 0:0.

      scsi0:1.ctkEnabled

      TRUE

      Specifies whether to allow the use of CTK files for the hard disk whose SCSI ID is 0:1.

      In the scsix:x.ctkEnabled parameter, x:x indicates the SCSI ID. Replace x:x with a SCSI ID based on your business requirements. In this topic, hard disks whose SCSI IDs are 0:0 and 0:1 are used. To query the SCSI IDs of hard disks in the VM, go to the Virtual Hardware tab of the Edit Settings page. adda

    6. Click OK. Then, right-click the VMware VM and choose Power > Power On to power on the VMware VM.

      If CBT is enabled, a xx-ctk.vmdk file is added to each virtual disk and snapshot disk. adad5

    Step 2: Create and start an incremental migration task

    Perform the following steps to create and start an incremental migration task in the SMC console. You do not need to stop your services that are running on the VM.

    1. Log on to the SMC console.

    2. In the left-side navigation pane, click Migration Sources.

    3. On the page that appears, click the VMware VM tab, find the migration source that you want to use, and then click Create Migration Job in the Actions column. ada56

      You can obtain the ID of the migration source from the SMC client, as shown in the following figure. Then, you can use the ID to find the migration source in the SMC console. For more information, see the "How do I find a migration source in the SMC console?" section in SMC FAQ. Obtain the ID of the migration source

    4. On the Create Migration Task page, turn on Automatic Incremental Synchronization, and configure the Synchronization Interval and Upperlimit of Reserved Images parameters. Configure other parameters based on your requirements and click OK.

      Automatic incremental synchronization

      You can configure the following parameters. For more information, see the "Step 3: Create and start a migration task" section in Migrate VMware VMs without agents (invitational preview).

      • Synchronization Interval: the time interval between two consecutive incremental migrations. The minimum interval is 1 hour, whereas the maximum interval is seven days.

      • Upperlimit of Reserved Images: the maximum number of reserved images. Valid values: 1 to 10. Each incremental migration generates an image. If the total number of generated images exceeds the upper limit, the earliest unused image is deleted.

      • Execution Method: the method to run the incremental migration task. In this example, Run Now is selected.

      The incremental migration task immediately starts after it is created. Data is migrated in the following way:

      1. If the task is run for the first time, SMC migrates all data from the VMware VM and generates a full image. You can use this image to create an Elastic Compute Service (ECS) instance for verification.

      2. After the first incremental migration is complete, SMC migrates incremental data and generates images at specific points in time based on the specified synchronization interval.

        Note

        The image generated for each incremental migration is a full image of the source VMware VM at a specific point in time. The image includes the incremental data and all data that has been migrated.

        In image names, CYCLE_X indicates that the image is generated by the Xth incremental migration. For example, if an image name contains CYCLE_2, the image is generated by the second incremental migration, as shown in the following figure. cycle

    Step 3: Stop the services on the VMware VM and run the incremental migration task

    To ensure that all data can be migrated to Alibaba Cloud, stop services on the VMware VM and run the incremental migration task during off-peak hours.

    1. In the SMC console, manually run the incremental migration task or wait for the task to automatically run. To manually run the incremental migration task, perform the following steps:

      1. On the VMware Agentless Migration tab of the Migration Jobs page, find the incremental migration task that you want to run.

      2. In the Actions column, choose more > Manual Incremental Migration.

        Manual incremental migration

      3. In the Start Migration Job message, click OK.

    2. On the VMware Agentless Migration tab of the Migration Jobs page, wait for the incremental migration task to complete.

      • If the incremental migration task is in the Pending state, the migration is successful. You can obtain the image that is generated during the migration. The image contains all the data of the first full migration and each subsequent incremental migration.

      • If the incremental migration task is in the InError state, the migration fails. You must check logs to fix the issue, and then run the task again. For information about common errors and solutions, see FAQ.

    What to do next

    After you obtain the latest full image, you can perform the following operations:

    • Create an ECS instance to verify the image. Perform the following steps:

      1. On the VMware Agentless Migration tab of the Migration Jobs page, find the incremental migration task for which you want to verify the image and click Create Instance in the Actions column.

      2. On the Custom Launch tab, select Custom Image as Image. The first full image is automatically selected. Configure other parameters based on your requirements and purchase the ECS instance. For more information, see Create an instance by using the wizard.

        Important

        The specifications of the ECS instance do not meet your business requirements if the following message appears: The predefined Custom Image parameter "m-bp1dtfnl25dbyleq****" cannot be populated. Manually select a value. To resolve the issue, change the instance type.

        adad566

      3. Remotely connect to the ECS instance and check the migrated data. For more information about how to remotely connect to an ECS instance, see Connection method overview.

    • Stop the incremental migration task. Perform the following steps:

      Note

      You can stop an incremental migration task only if the task is in the Synchronizing or Pending state.

      1. On the VMware Agentless Migration tab of the Migration Jobs page, find the incremental migration task that you want to stop and click more in the Actions column.

      2. Click Stop.

      3. In the Pause Migration Job message, click OK.

    • Delete the incremental migration task. Perform the following steps:

      1. On the VMware Agentless Migration tab of the Migration Jobs page, find the incremental migration task that you want to delete and click Delete in the Actions column.

      2. In the Delete Migration Job message, click OK.