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 Microsoft Entra apps created when you deploy the Azure Migrate appliance. | You need Contributor permissions on the Azure subscription. |
| Replication | You can simultaneously replicate a maximum of 500 VMs across multiple vCenter Servers (discovered from one appliance) using a scale-out appliance. In the portal, you can select up to 10 machines at once for replication. To replicate more machines, add in batches of 10. | Replication capacity increases by scaling the replication appliance. |
| 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 the Azure Migrate: Server Migration tool 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: 32 TB Maximum disks: 60 |
OS disk: 2 TB Data disk: 32 TB Maximum disks: 63 |
| Passthrough disks | Not supported | Supported |
| UEFI boot | Supported. | Supported. |
| Connectivity | Public internet ExpressRoute with Private peering ExpressRoute with Microsoft peering Site-to-site VPN |
Public internet ExpressRoute with Private peering ExpressRoute with Microsoft peering Site-to-site VPN |
Compare deployment steps
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 |
|---|---|---|---|
| Deploy the Azure Migrate appliance | A lightweight appliance that runs on a VMware VM. The appliance is used to discover and assess machines, and to migrate machines using agentless migration. |
Required. If you've already set up the appliance for assessment, you can use the same appliance for agentless migration. |
Not required. If you've set up an appliance for assessment, you can leave it in place, or remove it if you're done with assessment. |
| Use the Server Assessment tool | Assess machines with the Azure Migrate: Server Assessment tool. | Assessment is optional. | Assessment is optional. |
| Use the Migration tool | Add the Azure Migrate: Server Migration tool in the Azure Migrate project. | Required | Required |
| Prepare VMware for migration | Configure settings on VMware servers and VMs. | Required | Required |
| Install the Mobility service on VMs | Mobility service runs on each VM you want to replicate | Not required | Required |
| Deploy the replication appliance | The replication appliance is used for agent-based migration. It connects between the Mobility service running on VMs, and the Azure Migrate: Server Migration tool. | 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.