Migrate VMware VMs without agents - Server Migration Center

Server Migration Center (SMC) allows you to migrate VMware VMs without agents. This way, the migration does not modify the settings of the operating system of the migration source or occupy the computing resources of the operating system in the migration source. This can effectively eliminate your concerns about server security and performance. This topic describes how to use SMC to migrate VMware VMs without agents.

Note

You can also migrate VMware VMs by using agents. For more information, see Migrate a server to an ECS instance.

Migration scenarios

(Recommended) Migrate a server to an ECS custom image
If you have not purchased an ECS instance, you can migrate a server to an ECS custom image and then manually use the custom image to create an ECS instance.
Migrate a server to an ECS instance
If you have purchased an ECS instance and the configurations of the ECS instance such as the storage and operating system match those of the source server to be migrated, you can migrate the server to the ECS instance.
Warning
After the migration, the original data in the destination ECS instance is cleared. The data on the source server is not affected. We recommend that you do not use this method if the destination ECS instance contains important data.

Environment requirements

The following table describes the environment requirements that vary based on the Open Virtual Appliance (OVA) template.

OVA template

Configuration of a Server Migration Connector

Environment requirement for deploying a Server Migration Connector on vCenter Server

Environment requirement for deploying a Server Migration Connector on VMware ESXi

SMC VMware Connector 6.7 OVA

Number of vCPUs: four or more
Memory size: 8 GB or more
Disk space: 40 GB or more

vCenter Server version: 6.0, 6.5, or 6.7
Version of VMware ESXi on which the Server Migration Connector is deployed: 6.0, 6.5, or 6.7
Version of VMware ESXi on which the VMware VM to be migrated is deployed: 6.0, 6.5, or 6.7
Hardware version of the VMware VM to be migrated: 11, 12, 13, 14, or 15

VMware ESXi version: 6.0, 6.5, or 6.7
Hardware version of the VMware VM to be migrated: 11, 12, 13, 14, or 15

SMC VMware Connector 8.0 OVA

Number of vCPUs: four or more
Memory size: 8 GB or more
Disk space: 40 GB or more

vCenter Server version: 6.7, 7.0, or 8.0
Version of VMware ESXi on which the Server Migration Connector is deployed: 6.7, 7.0, or 8.0
Version of VMware ESXi on which the VMware VM to be migrated is deployed: 6.7, 7.0, or 8.0

Hardware version of the VMware VM to be migrated: 14, 15, 16, 17, 18, 19, 20, or 21

VMware ESXi version: 6.7, 7.0, or 8.0
Hardware version of the VMware VM to be migrated: 14, 15, 16, 17, 18, 19, 20, or 21

Required account permissions for vCenter Server and VMware ESXi

If you deploy a Server Migration Connector on vCenter Server, the account used to log on to VMware ESXi and the account used to log on to the VMware VM to be migrated must be granted the following permissions:
- Datastore > Browse datastore
- Datastore > Low-level file operations
- Host > Local operations > Create virtual machine
- Virtual machine > Change Configuration > Acquire disk lease
- Virtual machine > Change Configuration > Toggle disk change tracking
- Virtual machine > Provisioning > Allow virtual machine download
- Virtual machine > Provisioning > Allow disk access
- Virtual machine > Provisioning > Allow read-only disk access
- Virtual machine > Snapshot management > Create snapshot
- Virtual machine > Snapshot management > Remove Snapshot

If you deploy a Server Migration Connector on VMware ESXi, you must use an administrator account to log on to VMware ESXi.

Prerequisites

The preparations for the migration are complete. For more information, see Before you begin.
Important data is backed up to an image, snapshot, or storage device other than the destination instance to prevent data loss.
The following operations are complete if you want to migrate a server to an ECS instance:
- Back up the important data on the destination ECS instance to an image, snapshot, or storage device other than the instance.
- If your source server runs a Linux operating system, the destination instance must be a Linux distribution. If your source server runs a Windows operating system, the destination instance must run the same operating system.
- The number of data disks attached to the destination ECS instance is greater than or equal to that of data disks attached to the source server. Otherwise, the disk data of the source server cannot be migrated to the destination ECS instance. In this case, you must attach more data disks to the ECS instance. For more information, see Attach a data disk.
- The capacity of the system disk and data disks attached to the ECS instance is larger than or equal to that of the system disk and data disks attached to the source server. If you want to shrink the system disk and data disks attached to the source server, make sure that the capacity of the system disk and data disks attached to the destination ECS instance is larger than or equal to the size of the data on the system disk and data disks attached to the source server. Otherwise, data of the source server cannot be fully migrated to the destination ECS instance. In this case, you must scale up the data disks and system disk. For more information about how to resize a cloud disk, see Overview.

Procedure

Step 1: Create a Server Migration Connector

SMC provides OVA templates that are used to create a Server Migration Connector. In this step, download an OVA template, import the OVA template to your vCenter Server or VMware ESXi, and then deploy a Server Migration Connector by using the OVA template.

Note

Open Virtualization Format (OVF) is an open standard that provides an open source, secure, effective, extensible, and portable format for packaging and distributing software for VMs. An OVF package generally consists of .ovf, .mf, .cert, .vmdk, and .iso files. OVA is a single file distribution of the OVF file package.
VMware vSphere is a virtualization platform that transforms data centers into aggregated computing infrastructures that include CPU, storage, and network resources. VMware vSphere manages these infrastructures as a unified operating environment and provides you with tools to manage the data centers that are added to the environment. The two core components of VMware vSphere are VMware ESXi and vCenter Server. VMware ESXi is a virtualization platform that is used to create and run VMs and virtual devices. vCenter Server is a service that manages multiple hosts connected on a network and pools host resources.

Download and extract an OVA template

Go to the Import Migration source page. In the Description section, download an OVA template based on the version of your VMware ESXi or vCenter Server and decompress the downloaded package.

lQLPJxjJZIQrsxPMl80C7rBONH3msCozYwaTnoZxcjUA_750_151

Deploy a Server Migration Connector

Import the extracted OVA template to your VMware ESXi or vCenter Server and deploy a Server Migration Connector by using the OVA template. A Server Migration Connector can be deployed on vCenter Server or VMware ESXi. You can select the deployment environment based on your business requirements.

(Recommended) Deploy a Server Migration Connector on vCenter Server

Import the OVA template of a Server Migration Connector to vCenter Server and deploy the Server Migration Connector by using the OVA template. In this example, vCenter Server 6.7 is used. To deploy a Server Migration Connector on vCenter Server, perform the following steps:

Log on to vCenter Server. Find the vCenter Server host, right-click the name of the host, and then select Deploy OVF Template....
On the Deploy OVF Template page, follow the configuration wizard to create a VM.
1. Select the OVA template and click NEXT.
  Select Local file and click Browse... to select the extracted OVA template file.
2. Specify the VM name and installation location, and click NEXT.
  Enter the VM name in the Virtual machine name field and select the installation location.
3. Select a computing resource and click NEXT.
4. Confirm the template information and click NEXT.
5. Select the storage and click NEXT.
6. Select the destination network and click NEXT.
7. Confirm the configurations and click FINISH.
8. After the Server Migration Connector is deployed, right-click the Server Migration Connector and choose Power > Power On.
9. Configure the network environment to ensure that the Server Migration Connector can connect to port 443 of vCenter Server and port 902 of the ESXi host on which the VMware VM to be migrated resides. The preceding port numbers are the default port numbers.
10. On the Summary tab, obtain the IP addresses of the Server Migration Connector.

Deploy a Server Migration Connector on VMware ESXi

Import the OVA template of a Server Migration Connector to VMware ESXi and deploy the Server Migration Connector by using the OVA template. In this example, VMware ESXi 7.0 is used. To deploy a Server Migration Connector on VMware ESXi, perform the following steps:

Log on to VMware ESXi. In the left-side navigation pane, right-click Virtual Machines and select Create/Register VM.
In the Select creation type step, select Deploy a virtual machine from an OVF or OVA file and click Next.
In the Select OVF and VMDK files step, enter a VM name, click Click to select files or drag/drop, select the downloaded OVA template, and then click Next.
In the Select storage step, click Next.
In the Deployment options step, click Next.
In the Ready to complete step, click Finish.
Wait until the VM is deployed. The IP address of the Server Migration Connector is displayed in the General Information section. By default, Dynamic Host Configuration Protocol (DHCP) is configured in the network settings of the Server Migration Connector. You can modify the network settings based on your business requirements.
Configure the network environment to ensure that the Server Migration Connector can connect to port 443 and port 902 of VMware ESXi. The preceding port numbers are the default port numbers.

Step 2: Import the information about the VMware VM to be migrated

Log on to the Server Migration Connector, configure the VMware VM to be migrated, and then import the information about the VMware VM to be migrated by running commands.

Configure the VMware VM to be migrated

Log on to the Server Migration Connector.
In this example, an SSH remote connection is established. Perform the following steps:
On a terminal from which the Server Migration Connector is accessible over a network, run the following command to connect to the Server Migration Connector. The default username is root, and the default password is left empty.
```
ssh root@<IP address of the Server Migration Connector>
```
Important
For account security, we recommend that you change your password at the earliest opportunity.
Run the following command to check whether the time on the Server Migration Connector is accurate:
```
date
```
If the time is inaccurate, you can run the ntpdate command to calibrate the time. In this topic, the time server at 0.asia.pool.ntp.org is used.
```
ntpdate 0.asia.pool.ntp.org
hwclock --systohc
```
Warning
If the time is inaccurate, the information about the migration source fails to be imported.

Run the following commands to configure the VMware VM to be migrated on your vCenter Server or VMware ESXi:

Note

In this step, you can obtain all the hosts and VMs in the environment. If you already know the names of the hosts or VMs that you want to configure, skip this step and directly specify the names of the hosts or VMs. For more information, see the "How do I migrate the specified VM or a VM on the specified host by performing VMware migration without agents?" section of the FAQ topic.

cd /root/smc
bash configure.sh

Configure the IP address, username, password, and port number of vCenter Server or VMware ESXi in sequence. We recommend that you use the default port 443. Sample command output:

[root@localhost ~]# cd /root/smc
[root@localhost smc]# ./configure.sh
Please input vCenter/ESXi IP:192.168.XX.XX
Please input username:administr****@vsphere.local
Please input password:
Please input port number(default 443):443

The "Connect success" message is displayed, and a list of hosts is generated. Enter the ID of the host on which the VMware VM to be migrated resides. You must select a host that is in the Connected state. If an asterisk (*) is displayed in the Connected column of a host, the host is connected.

Test to connect the vCenter/ESXi...
Connect success!
save to ./vmware_connect_config.json
========Aliyun SMC VMware Configure Tool 1.2========
Connect success!
 Getting host list progress:
 [>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>100.00%]time: 1.0s


Host List:
------------------------------------------------------------------------
ID      Name                              Version            Connected
1       192.168.XX.XX                     6.7.0                  *
2       192.168.XX.XX                     7.0.3                  *
------------------------------------------------------------------------
Please input the ID of Host(input 0 to exit):1

After you enter a host ID, a list of VMs is generated. Enter the ID of the VMware VM to be migrated. You must select a VM that is in the Connected state. If an asterisk (*) is displayed in the Connected column of a VM, the VM is connected.

Test to connect 192.168.XX.XX
Connect success!
 Getting vm list progress:
 [>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>100.00%]time: 2.3s


VM List of 192.168.XX.XX:
------------------------------------------------------------------------
ID      Name                               Connected      CBT      Add
1080    test1                                  *
1084    win16bios                              *
1011    centos7-bios-2                         *
3008    centos7-uefi                           *
2001    centos-hw10                            *
------------------------------------------------------------------------
Please input the ID of VM to be migrated (input 0 to exit):1084

Select the architecture of the VM to be migrated.

--------------------------------------------------------------
0    x86_64
1    i386
2    arm64
--------------------------------------------------------------
Please choose the architecture:0

If the operating system recognized by the system is incorrect, enter the number that corresponds to the actual operating system in the list. For example, you can enter 10 to select the Windows Server 2016 operating system.

Note

The preset operating system when a VM is created on vCenter Server may be incorrect. You must confirm the operating system of the VM.

------------------------------------------------------------------------
0	CentOS
1	Ubuntu
2	SUSE
3	OpenSUSE
4	Debian
5	RedHat
6	Others Linux
7	Windows Server 2003
8	Windows Server 2008
9	Windows Server 2012
10	Windows Server 2016
11	Windows Server 2019
12	Windows Server 2022
------------------------------------------------------------------------
Current OS [Apple macOS 10.14 (64-bit)] is invalid, please choose the OS of VM:10

If an asterisk (*) is displayed in the Add column of the VM, the VM is added to the migration list.

VM List of 192.168.XX.XX:
--------------------------------------------------------------
ID      Name                     Connected      CBT      Add  
481     TEST_CLONE_1                 *      
389     win16bios                    *                    *  
338     hanjun_test_001              *  
386     Aliyun_SMC_Agent_6.5         *  
393     win16uefi   
--------------------------------------------------------------
Please input the ID of VM to be migrated (input 0 to exit):0

If you want to migrate multiple VMs, enter the IDs of the VMs to be migrated.
If you want to migrate only one VM, enter 0 and return to the host list. If you want to migrate VMs on other hosts, repeat the preceding steps. Otherwise, enter 0 to exit the configuration.

Optional. Run the following command to view the generated vmware_connect_config.json and vmware_migrate_config.json files:

ll

A command output similar to the following one is returned:

[root@localhost smc]# ll
total 5588
drwxrwxrwx. 4 root root     239 Oct 17 17:27 Check
-rwxrwxrwx. 1 root root    6884 Oct 14 15:54 client_data
-rwxrwxrwx. 1 root root     151 Oct 14 17:47 configure.sh
drwxrwxrwx. 2 root root      72 Nov  1 01:15 dist
-rwxrwxrwx. 1 root root   38878 Oct 14 15:54 EULA
drwxrwxrwx. 2 root root    4096 Oct 17 17:27 Excludes
-rwxrwxrwx. 1 root root 5633792 Oct 31 19:43 go2aliyun_client
-rwxrwxrwx. 1 root root     146 Oct 14 15:54 user_config.json
-rw-r--r--. 1 root root     263 Nov 10 18:05 vmware_connect_config.json
-rw-r--r--. 1 root root   18406 Nov 10 18:07 vmware_migrate_config.json

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

After you log on to the Server Migration Connector, start the SMC client and import the information about the VMware VM to be migrated to the SMC console by running commands.

Warning

When the SMC client is running, do not perform operations on the VMware VM to be migrated, such as shutting down the VMware VM, restarting the VMware VM, and creating or deleting snapshots for the VMware VM. If you create or delete snapshots for the VMware VM to be migrated, the migration may fail. If the migration fails, run the ./dist/migrate_configure command in the /root/smc home directory of the SMC client to obtain the VM configurations again. Then, run the ./go2aliyun_client --jobtype=3 command to start a new SMC client.
During the synchronization phase of the migration task, the SMC client automatically creates a snapshot named smc_current time for the VM to be migrated, for example, smc_2024-04-01-12:00:32, and automatically deletes the snapshot after the synchronization is completed. If you manually delete the task before the synchronization is completed, the snapshot will remain. For more information, see the following solutions:
- Solution 1: Manually delete a snapshot.
- Solution 2: Run the following command to retrieve the VM configuration in the SMC client home directory and rerun the SMC client.
```
cd /root/smc
./dist/migrate_configure    #Retrieve the VM configuration.
./go2aliyun_client --jobtype=3   #Restart the SMC client.
```

Log on to SMC console-Agentless Migration of VMware VMs.
On the Agentless Migration of VMware VMs page, click Import Migration source.

On the Import Migration source page, configure the parameters.

The following table describes the parameters.

Parameter	Description
Migration Source Type	The type of the migration source. Select VMware VM from the drop-down list.
Import Method	The method that is used to import the information about the migration source. By default, Use Server Migration Connector to Import VMware VM is selected and cannot be changed.
Description	The description of the procedure for importing the information about a migration source.

Obtain the SMC access token or AccessKey pair.
- Obtain the SMC access token: recommended. An SMC access token consists of an access token ID and an access token code. If you do not have an SMC access token, go to the Import Migration source page in the SMC console. In the Description section, click Generate and copy the generated access token ID and access token code.
- Obtain the AccessKey pair: An 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 Obtain an AccessKey pair.
- Log on to the Server Migration Connector and run the following commands to import the information about the VMware VM:
```
chmod +x ./go2aliyun_client
./go2aliyun_client --jobtype=3
```
  Enter the SMC access token or AccessKey pair as prompted. In this example, the SMC access token is used. The returned information is similar to the following content. If the Import Source Server [s-bp14zd35128xgjdbh****] Successfully message is displayed, the information about the VMware VM to be migrated is imported.
- On the Agentless Migration of VMware VMs page in the SMC console, view the status of the migration source in the Real-time Migration Status column.
  - If the status of the migration source is Online, the information about the migration source is imported.
  - If the migration source is in another state, the information fails to be imported. In this case, troubleshoot the failure based on the following solutions and import the information about the migration source again:
    - Troubleshoot the failure based on the message displayed in the SMC console or the log file in the directory in which the SMC client is installed. By default, the SMC client is installed in the C:\smc directory.
    - For more information about frequently asked questions (FAQ) and solutions, see FAQ about Server Migration Center (SMC) and Errors occurred during a server migration.

Step 3: Create and start a migration job

In the SMC console, create and start a migration job as prompted. Valid values of the Destination Type parameter when you create the migration job:

(Recommended) ECS Image: You can migrate the VMware VM to an ECS image and then create an ECS instance by using the image.
ECS Instance: You can migrate the VMware VM to an ECS instance that you have purchased. The storage system and operating system of the VMware VM must be compatible with those of the destination ECS instance.
Warning
After a migration job is created, all original data is deleted from the destination ECS instance. However, the system does not delete data from the VMware VM. If the destination ECS instance contains important data, we recommend that you do not directly migrate the VMware VM to the destination instance.

Log on to SMC console-Agentless Migration of VMware VMs.
Find the migration source that you want to manage and click Start Migration in the Actions column.

Configure the parameters and click Start Migration.

Configure the basic parameters described in the following table.

Parameter	Description	Example
Migration Job Name	The name of the migration job.	VMware migration without agents
Job Description	The description of the migration job.	test
Destination Type	Required. The type of the destination. Select a destination type based on the actual migration scenario. ECS Image Migrate the source server to an ECS custom image and then use the custom image to create an ECS instance. If you set the Destination Type parameter to ECS Image, the following parameters are displayed: Destination Region: the Alibaba Cloud region to which you want to migrate the source server. This parameter is required. For more information about regions, see Regions and zones. Image Name: the name of the destination custom image generated by SMC for the source server. ECS Instance Migrate the source server to an existing ECS instance whose configurations such as storage and operating system match those of the source server. If you set the Destination Type parameter to ECS Instance, the following parameters are displayed: Destination Region: the Alibaba Cloud region to which you want to migrate the source server. This parameter is required. For more information about regions, see Regions and zones. Destination Instance: the ECS instance that is used as the destination instance.	ECS Image
Execution Method	The mode in which the migration job is run. Valid values: Migrate Now: The migration job starts immediately after it is created. This is the default value. Migrate Later: The migration job automatically starts at the specified time after it is created. Note The earliest time that you can specify to run a migration job is 10 minutes after the job is created. Create Only: After the migration job is created, you must click Start Migration Job in the Actions column to manually start the migration job.	Keep the default setting
Automatic Incremental Synchronization	Specifies whether SMC automatically synchronizes incremental data of the migration source to Alibaba Cloud. By default, this feature is disabled. Note If you set the Destination Type parameter to ECS Instance and configure the Destination Instance parameter, this feature is not supported. If you enable this feature, you must configure the following parameters: Synchronization Interval: the interval at which SMC automatically synchronizes incremental data to Alibaba Cloud. Maximum Reserved Images: the maximum number of images that can be retained during incremental data synchronization. SMC automatically synchronizes incremental data to Alibaba Cloud at the specified interval. For more information about the best practices for incremental data synchronization, see Migrate incremental data from a VMware VM without an agent.	Keep the default setting

Configure the disk parameters described in the following table.

Parameter

Description

Example

Destination Disk Size (GiB)

The disk configurations of the destination instance. Configure the following parameters based on your business requirements:

System disk

The size of the system disk of the destination instance. Unit: GiB. Valid values: 20 to 2048. The size of the destination system disk must be larger than the amount of data on the source system disk. For example, if the total size of the source system disk is 400 GiB but the size of data stored on this disk is only 100 GiB, you must set this parameter to a value greater than 100.

Note

The default value of this parameter is the size of the source system disk. We recommend that you retain the default value or specify a greater value.

Data disk

Data Disk <N>: the size of the data disk of the destination instance. Unit: GiB. Valid values: 20 to 32768.

If you select the Data Disk <N> check box, a destination data disk is generated.
<N> indicates the serial number of the data disk.
The size of the destination data disk must be larger than the amount of data on the source data disk. For example, if the total size of the source data disk is 500 GiB but the size of data stored on this disk is only 100 GiB, you must set this parameter to a value greater than 100.

Note

If your migration source has no data disk or no data disk is attached to the migration source, the Data Disk parameters are not displayed. For more information, see the "Why are the data disk parameters of a migration source not displayed in the Create Migration Job dialog box? What do I do?" section of the FAQ topic.

Keep the default setting

Optional. Click Expert Mode to configure advanced parameters such as Network Type and Compression Ratio. The following table describes the advanced parameters.

Parameter	Description	Example
Network Type	The type of network that is used to migrate data from the source server to the intermediate instance. By default, data is migrated over the Internet. During the migration, SMC creates an intermediate instance that connects to a vSwitch in a VPC. If you select Public Network, a public IP address is assigned to the intermediate instance. Public Network (default value) SMC migrates data to the intermediate instance over the Internet. If you select Public Network, make sure that the source server can access the Internet. You can determine whether to specify a VPC and a vSwitch based on your business requirements. If you specify a VPC and a vSwitch, SMC creates an intermediate instance that connects to the specified VPC and vSwitch. If you do not specify a VPC or vSwitch, SMC creates an intermediate instance that connects to the VPC and vSwitch automatically created by the system. VPC SMC migrates data to the intermediate instance over a VPC. If you select VPC, you must specify a VPC and a vSwitch and make sure that the source server can connect to the VPC. Note If your server in a data center, your VM, or your third-party cloud server can connect to a VPC, we recommend that you select this network type to migrate data. Compared with migration over the Internet, migration over a VPC is more efficient and stable. You can use VPN Gateway, Express Connect, or SAG to connect a migration source to a VPC. For more information, see Connect a data center to a VPC.	Keep the default setting
Transmission Speed Limit	The maximum network transfer speed during the migration. Unit: Mbit/s. If you set the Compression Ratio parameter to a value greater than 0, the actual network transfer speed, which is the transfer speed of compressed data, is lower than the speed displayed in the Real-time Migration Status column.	Keep the default setting
Compression Ratio	The compression ratio of the data to be migrated. Set the compression ratio based on your business requirements. If the bandwidth is limited, a high compression ratio improves the transmission efficiency. If a high bandwidth is available, we recommend that you do not compress data. Data compression consumes CPU resources of the migration source. Valid values: 0 to 10. Default value: 7. A value of 0 indicates that data is not compressed.	Keep the default setting
Checksum Verification	Specifies whether to verify data integrity by using a checksum. By default, this feature is disabled. If you enable this feature, data integrity is ensured, but transmission speed may be reduced.	Keep the default setting
SSL-Encrypted Transmission	Using SSL encryption for data migration enhances security and ensures data integrity. By default, this feature is enabled.	Keep the default setting
License Type	The license type. Valid values: Alibaba Cloud (default): Only a Microsoft Windows Server license is supported. After migration, you are charged license fees for an image when you use the image to create an ECS instance in Hong Kong (China) and regions outside China, and the image is automatically activated. The specific cost is subject to the information displayed when the instance is created. BYOL: SMC allows you to bring your own license (BYOL). You can bring your own Microsoft license or register with Red Hat Enterprise Linux and SUSE Linux Enterprise Server. After migration, you are not charged license fees for an image when you use the image to create an ECS instance. You can use your own license for activation. Note If you have created an ECS instance, you can quickly purchase software licenses such as Red Hat Enterprise Linux and SUSE Linux Enterprise Server for specified ECS instances supported by Alibaba Cloud. For more information, see Purchase a software license for an ECS instance (invitational preview).	Keep the default setting
Image Check	Specifies whether to enable the image check feature. The image check feature checks whether an image is valid and whether the image can be used to create full-featured ECS instances. You can use the image check feature when you migrate servers or VMware VMs without agents. This feature helps you identify potential issues in images or ECS instances after the migration job is complete, and provides solutions to the identified issues. This helps you improve the success rate of starting ECS instances. For more information, see Configure image check.	Keep the default setting
Migration Job Tags	The tags that you specify for the migration job. Each tag contains a key and a value. You can use tags to query and manage migration jobs. For more information, see Use tags to manage migration sources and migration jobs and Use tags to implement fine-grained access control. Note You can specify up to 20 tags for a migration job.	Keep the default setting
Intermediate Instance Type	The type of the intermediate instance. Select an intermediate instance type based on your business requirements. This parameter is available only if you set the Destination Type parameter to ECS Image. The instance type of the intermediate instance is automatically selected. If you specify an instance type, SMC creates an intermediate instance of the specified type. If the specified instance type is unavailable, the migration job fails to be created. If you do not specify an instance type, SMC automatically creates an intermediate instance. Important Do not stop, start, restart, or release the intermediate instance during the migration to prevent migration failures. After the migration is complete, SMC automatically releases the intermediate instance.

In the message that appears, read the migration notes and click Got It.
On the Agentless Migration of VMware VMs page, view the real-time status of the migration job.
The amount of time required for data transmission is subject to factors such as the data size of the migration source and network bandwidth. Wait until the migration job is complete.
To pause the migration job when the migration job is in the Synchronizing state, click Pause in the Actions column.
Optional. To view details about the migration, perform the following steps:
View migration details
In the Migration Source ID /Name column of the destination migration source, click the migration source ID to view the job details.

Step 4: (Optional) Migrate another VMware VM

If you specify multiple VM IDs when you configure the VMware VM to be migrated, you can close the SMC client process after the current VMware VM is migrated, and then migrate another VMware VM. To migrate another VMware VM, perform the following steps:

Log on to the Server Migration Connector. For more information, see the Configure the VMware VM to be migrated section in Step 2 of this topic.
Press Ctrl+C to exit the current SMC client process that is running. Then, run the following command to close the SMC client process:
```
./dist/finish 1
```
Run the following command to start a new SMC client. Then, migrate another VMware VM.
```
./go2aliyun_client --jobtype=3
```

Verify the migration result

If Completed is displayed in the Real-time Migration Status column, the migration is successful.
- If you set the Destination Type parameter to ECS Image for the migration job, you can verify the migration result in the following way:
  After the migration is complete, an Alibaba Cloud custom image is generated. You can use your pointer to slide the scrollbar at the bottom to the right and click View Report in the Migration Deliverables column to view the check result of the image. For more information, see View the image check results step of the "Configure image check" topic.
  (Recommended) Manually verify the migration result
  You can click Create Instance in the Actions column to go to the ECS instance creation page in the ECS console. The custom ECS image created by the migration job is selected by default for you to create an ECS instance. For more information, see Create an instance by using a custom image.
  Use the automatic migration result verification feature
  Note
  To use this feature, you must install the Cloud Assistant Agent in your instance, and the system version of the instance must support this feature. For more information, see Install Cloud Assistant Agent.
  This feature uses the ACS-SMC-CreateAndVerifyInstance template provided by Alibaba Cloud CloudOps Orchestration Service (OOS) to automatically verify whether the image generated by the migration job can be used to create an ECS instance and whether the ECS instance can start as expected.
  Click Verify Migration Result in the Actions column.
  In the dialog box that appears, read the instructions on the verification process and click Verify Now.
  You can also click Customize Verification Parameters to configure the parameters.
  In the Verify Migration Result column, view the verification result. Valid values:
  Verified: indicates that the migration is successful. You can click Details to check the verification result.
  Not Verified: indicates that the migration failed. You can click View Cause to troubleshoot the failure.
  You can also click the icon in the Actions column and select View Verification Records in OOS Console to view the template history.
- If you set the Destination Type parameter to ECS Instance for the migration job, you can click View Destination Instance in the Actions column to go to the details page of the destination ECS instance to verify the migration result.
After the server is migrated, you must perform the following operations to ensure normal operation of your business:
- Verify the integrity and correctness of the data. For more information, see the How do I check my system after I migrate a Linux server? or How do I check my system after I migrate a Windows server? section of the "FAQ" topic.
- Manually start the applications and services after the migration if automatic start is not enabled for the applications and services on the source server.
- The IP address changes after the migration job is complete. If the service involves the configuration of the IP address, modify the domain name resolution and ICP filing after the migration.
  If a domain name has been bound to the source server, the public IP address of the server is changed after the migration. In this case, you must resolve the domain name to the new public IP address of the server. For more information, see Add an A record for a website domain name.
  If you want to keep the private IP address unchanged, you can modify the private IP address after the migration is complete.
  Migrate a server to an ECS Image: Modify the private IP address when creating an ECS instance. For more information, see Specify the primary private IPv4 address when creating an ECS instance.
  Migrate a server to a Destination Instance: If you have not modified the IPv4 private network address in the advanced configuration of the Migration Settings step, you can also modify the IPv4 private network address after migration. For more information, see Change the primary private IPv4 address for an existing ECS instance.
If the migration test is in the state, the migration test failed.
In this case, you need to check the test report, fix the test items that are in the Critical state, and then perform a test again. For more information, see Configure a migration test.
If Error is displayed in the Real-time Migration Status column, the migration failed.
In this case, you need to perform the following operations:
1. Click Troubleshoot Errors in the Actions column and fix issues based on the error code and description. For more information, see FAQ about Server Migration Center (SMC) and Errors occurred during a server migration.
2. After the issues are fixed, click Retry Migration in the Actions column of the migration job.
  The migration job resumes from the point where it was suspended.
  Important
  If the intermediate instance is released, you must create another migration job. For more information, see the What do I do if I release an intermediate instance by accident? section of the "FAQ" topic.

Clear resources

Migrate a server to an ECS image
During the migration, SMC creates a temporary pay-as-you-go intermediate instance named No_Delete_SMC_Transition_Instance within the destination Alibaba Cloud account. The method to clear resources depends on whether the migration is successful.
- If the migration is successful, the intermediate instance is automatically released. No manual operation is required.
- If the migration failed, the intermediate instance is not automatically released and incurs fees as long as the migration job exists. You can release the intermediate instance in one of the following ways to reduce costs:
  - If you no longer need the migration job, click the ID the migration job. On the job details page, click > Clear migration task in the Actions column in the Migration Jobs section to delete the migration job and release the intermediate instance at a time.
  - Manually release the intermediate instance. For more information, see Release an instance.
Migrate a server to an ECS instance
During the migration, SMC creates a temporary pay-as-you-go intermediate cloud disk named SMC_Temp_Disk in the destination instance. The method to clear resources depends on whether the migration is successful.
- If the migration is successful, the intermediate cloud disk is automatically released. No manual operation is required.
- If the migration failed, the intermediate cloud disk is not automatically released and incurs fees as long as the migration job exists. You can release the intermediate cloud disk in one of the following ways to reduce costs:
  - If you no longer need the migration job, click the ID of the migration job. On the job details page, click > Clear migration task in the Actions column in the Migration Jobs section to delete the migration job and release the intermediate cloud disk at a time.
  - Manually release the intermediate instance. For more information, see Release a disk.

Related operations

Migrate incremental data
If you need to migrate incremental data multiple times, you can initiate incremental data migration multiple times at custom intervals after the first full migration is complete. This synchronizes the incremental data generated by the source server to Alibaba Cloud and reduces the suspension time and delivery time of the services provided by the source server. For more information, see Migrate incremental data from a VMware VM without an agent.
Configure multiple migration jobs
If you want to migrate a large number of VMware VMs, you can configure multiple jobs to migrate VMs at a time to improve migration efficiency.
Important
You can close the SMC client process for a VMware VM and migrate another VMware VM only after the first VMware VM is migrated. If you close the SMC client process for a VMware VM whose migration is in progress, the VMware VM fails to be migrated.
1. Create multiple Server Migration Connectors.
  You can run up to five SMC clients on each Server Migration Connector. If you require more than five SMC clients, you can deploy multiple Server Migration Connectors by cloning a Server Migration Connector or using the OVA template based on the remaining available resources in the current VMware environment. Then, run the SMC clients on different Server Migration Connectors. In this example, a Server Migration Connector is cloned.
  1. Right-click the Server Migration Connector to be cloned and choose Clone > Clone to Virtual Machine.
  2. Specify the VM name, installation location, computing resources, storage space, and clone options in sequence.
    For more information, see the Step 1: Create a Server Migration Connector section of this topic.
2. Log on to the Server Migration Connector. For more information, see the Configure the VMware VM to be migrated section in Step 2 of this topic.
3. Run the following commands to obtain multiple SMC clients for each Server Migration Connector.
  You can run up to five SMC clients on each Server Migration Connector at a time. You can copy multiple SMC client files based on your business requirements.
  cd /root cp -r smc smc2 cp -r smc smc3 cp -r smc smc4 cp -r smc smc5 mv smc smc1
  Important
  You can run up to five SMC clients on each Server Migration Connector at a time.
4. Run the following commands to run the configuration script for each Server Migration Connector.
  If you run multiple SMC clients on a Server Migration Connector, you can go to the directory of the specified SMC client and run the bash configure.sh command to run the configuration script for the specified SMC client. In this example, the second SMC client is used.
  cd /root/smc2 bash configure.sh
  For more information about how to run the configuration script, see the Configure the VMware VM to be migrated section in Step 2 of this topic.
5. Run the following command to view the processes of the SMC clients that are running:
  ps -ef | grep smcvmware_client
  A command output similar to the following one is returned.
  Note
  When multiple SMC clients are running, the SMC client processes are named based on the time sequence in which they start, such as smcvmware_client_1, smcvmware_client_2, ..., and smcvmware_client_N.
6. After the migration job corresponding to each SMC client is complete, exit the SMC client process by pressing Ctrl+C. Then, run the following command to close the current SMC client process:
  ./dist/finish N
  In the command, N indicates the process sequence and must be replaced with the actual value, such as 1 or 2.
7. Run the following command to start a new SMC client. Then, migrate another VMware VM.
  ./go2aliyun_client --jobtype=3

Server Migration Center:Migrate VMware VMs without agents

Migration scenarios

Environment requirements

Required account permissions for vCenter Server and VMware ESXi

Prerequisites

Procedure

Step 1: Create a Server Migration Connector

Download and extract an OVA template

Deploy a Server Migration Connector

(Recommended) Deploy a Server Migration Connector on vCenter Server

Deploy a Server Migration Connector on VMware ESXi

Step 2: Import the information about the VMware VM to be migrated

Configure the VMware VM to be migrated

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

Step 3: Create and start a migration job

ECS Image

ECS Instance

System disk

Data disk

Public Network (default value)

VPC

Step 4: (Optional) Migrate another VMware VM

Verify the migration result

(Recommended) Manually verify the migration result

Use the automatic migration result verification feature

Clear resources

Related operations