Migrating a virtual machine instance to another node

Manually initiate a live migration of a virtual machine instance to another node using either the web console or the CLI.

If a virtual machine uses a host model CPU, you can perform live migration of that virtual machine only between nodes that support its host CPU model.

Initiating live migration of a virtual machine instance in the web console

Migrate a running virtual machine instance to a different node in the cluster.

The Migrate action is visible to all users but only admin users can initiate a virtual machine migration.

Procedure

  1. In the OKD console, click Virtualization → VirtualMachines from the side menu.

  2. You can initiate the migration from this page, which makes it easier to perform actions on multiple virtual machines on the same page, or from the VirtualMachine details page where you can view comprehensive details of the selected virtual machine:

    • Click the Options menu kebab next to the virtual machine and select Migrate.

    • Click the virtual machine name to open the VirtualMachine details page and click Actions → Migrate.

  3. Click Migrate to migrate the virtual machine to another node.

Monitoring live migration by using the web console

You can monitor the progress of all live migrations on the Overview → Migrations tab in the web console.

You can view the migration metrics of a virtual machine on the VirtualMachine details → Metrics tab in the web console.

Initiating live migration of a virtual machine instance in the CLI

Initiate a live migration of a running virtual machine instance by creating a VirtualMachineInstanceMigration object in the cluster and referencing the name of the virtual machine instance.

Procedure

  1. Create a VirtualMachineInstanceMigration configuration file for the virtual machine instance to migrate. For example, vmi-migrate.yaml:

    1. apiVersion: kubevirt.io/v1
    2. kind: VirtualMachineInstanceMigration
    3. metadata:
    4.   name: migration-job
    5. spec:
    6.   vmiName: vmi-fedora

  2. Create the object in the cluster by running the following command:

    1. $ oc create -f vmi-migrate.yaml

The VirtualMachineInstanceMigration object triggers a live migration of the virtual machine instance. This object exists in the cluster for as long as the virtual machine instance is running, unless manually deleted.

Monitoring live migration of a virtual machine instance in the CLI

The status of the virtual machine migration is stored in the Status component of the VirtualMachineInstance configuration.

Procedure

  • Use the oc describe command on the migrating virtual machine instance:

    1. $ oc describe vmi vmi-fedora

    Example output

    1. # ...
    2. Status:
    3.   Conditions:
    4.     Last Probe Time:       <nil>
    5.     Last Transition Time:  <nil>
    6.     Status:                True
    7.     Type:                  LiveMigratable
    8.   Migration Method:  LiveMigration
    9.   Migration State:
    10.     Completed:                    true
    11.     End Timestamp:                2018-12-24T06:19:42Z
    12.     Migration UID:                d78c8962-0743-11e9-a540-fa163e0c69f1
    13.     Source Node:                  node2.example.com
    14.     Start Timestamp:              2018-12-24T06:19:35Z
    15.     Target Node:                  node1.example.com
    16.     Target Node Address:          10.9.0.18:43891
    17.     Target Node Domain Detected:  true

Additional resources