Chapter 5. Migration Toolkit for Virtualization 2.0

You can migrate virtual machines (VMs) from VMware vSphere with the Migration Toolkit for Virtualization (MTV).

The release notes describe new features and enhancements, known issues, and technical changes.

5.1. New features and enhancements

This release adds the following features and improvements.

Warm migration

Warm migration reduces downtime by copying most of the VM data during a precopy stage while the VMs are running. During the cutover stage, the VMs are stopped and the rest of the data is copied.

Cancel migration

You can cancel an entire migration plan or individual VMs while a migration is in progress. A canceled migration plan can be restarted in order to migrate the remaining VMs.

Migration network

You can select a migration network for the source and target providers for improved performance. By default, data is copied using the VMware administration network and the Red Hat OpenShift pod network.

Validation service

The validation service checks source VMs for issues that might affect migration and flags the VMs with concerns in the migration plan.

Important

The validation service is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information about the support scope of Red Hat Technology Preview features, see https://access.redhat.com/support/offerings/techpreview/.

5.2. Known issues

This section describes known issues and mitigations.

QEMU guest agent is not installed on migrated VMs

The QEMU guest agent is not installed on migrated VMs. Workaround: Install the QEMU guest agent with a post-migration hook. (BZ#2018062)

Network map displays a "Destination network not found" error

If the network map remains in a NotReady state and the NetworkMap manifest displays a Destination network not found error, the cause is a missing network attachment definition. You must create a network attachment definition for each additional destination network before you create the network map. (BZ#1971259)

Warm migration gets stuck during third precopy

Warm migration uses changed block tracking snapshots to copy data during the precopy stage. The snapshots are created at one-hour intervals by default. When a snapshot is created, its contents are copied to the destination cluster. However, when the third snapshot is created, the first snapshot is deleted and the block tracking is lost. (BZ#1969894)

You can do one of the following to mitigate this issue:

  • Start the cutover stage no more than one hour after the precopy stage begins so that only one internal snapshot is created.

  • Increase the snapshot interval in the vm-import-controller-config config map to 720 minutes: 

    $ oc patch configmap/vm-import-controller-config \
  -n openshift-cnv -p '{"data": \
  {"warmImport.intervalMinutes": "720"}}'