Select a VMware migration option

You can migrate VMware VMs to Azure using the Azure Migrate Server Migration tool. This tool offers a couple of options for VMware VM migration:

  • Migration using agentless replication. Migrate VMs without needing to install anything on them.
  • Migration with an agent for replication. Install an agent on the VM for replication.

Compare migration methods

Use these selected comparisons to help you decide which method to use. You can also review full support requirements for agentless and agent-based migration.

Setting Agentless Agent-based
Azure permissions You need permissions to create an Azure Migrate project, and to register Azure AD apps created when you deploy the Azure Migrate appliance. You need Contributor permissions on the Azure subscription.
Simultaneous replication A maximum of 100 VMs can be simultaneously replicated from a vCenter Server.
If you have more than 50 VMs for migration, create multiple batches of VMs.
Replicating more at a single time will impact performance.
Appliance deployment The Azure Migrate appliance is deployed on-premises. The Azure Migrate Replication appliance is deployed on-premises.
Site Recovery compatibility Compatible. You can't replicate with Azure Migrate Server Migration if you've set up replication for a machine using Site Recovery.
Target disk Managed disks Managed disks
Disk limits OS disk: 2 TB

Data disk: 4 TB

Maximum disks: 60
OS disk: 2 TB

Data disk: 8 TB

Maximum disks: 63
Passthrough disks Not supported Supported
UEFI boot Not supported The migrated VM in Azure will be automatically converted to a BIOS boot VM.

The OS disk should have up to four partitions, and volumes should be formatted with NTFS.

Deployment steps comparison

After reviewing the limitations, understanding the steps involved in deploying each solution might help you decide which option to choose.

Task Details Agentless Agent-based
Assessment Assess servers before migration. Assessment is optional. We suggest that you assess machines before you migrate them, but you don't have to.

For assessment, Azure Migrate sets up a lightweight appliance to discover and assess VMs.
If you run an agentless migration after assessment, the same Azure Migrate appliance set up for assessment is used for agentless migration. If you run an agent-based migration after assessment, the appliance set up for assessment isn't used during agentless migration. You can leave the appliance in place, or remove it if you don't want to do further discovery and assessment.
Prepare VMware servers and VMs for migration Configure a number of settings on VMware servers and VMs. Required Required
Add the Server Migration tool Add the Azure Migrate Server Migration tool in the Azure Migrate project. Required Required
Deploy the Azure Migrate appliance Set up a lightweight appliance on a VMware VM for VM discovery and assessment. Required Not required.
Install the Mobility service on VMs Install the Mobility service on each VM you want to replicate Not required Required
Deploy the Azure Migrate Server Migration replication appliance Set up an appliance on a VMware VM to discover VMs, and bridge between the Mobility service running on VMs and Azure Migrate Server Migration Not required Required
Replicate VMs. Enable VM replication. Configure replication settings and select VMs to replicate Required Required
Run a test migration Run a test migration to make sure everything's working as expected. Required Required
Run a full migration Migrate the VMs. Required Required

Next steps

Migrate VMware VMs with agentless migration.