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4.5. Migrating with virt-manager

This section covers migrating a KVM guest virtual machine with virt-manager from one host physical machine to another.
  1. Open virt-manager

    Open virt-manager. Choose ApplicationsSystem ToolsVirtual Machine Manager from the main menu bar to launch virt-manager.
    Virt-Manager main menu

    Figure 4.1. Virt-Manager main menu

  2. Connect to the target host physical machine

    Connect to the target host physical machine by clicking on the File menu, then click Add Connection.
    Open Add Connection window

    Figure 4.2. Open Add Connection window

  3. Add connection

    The Add Connection window appears.
    Adding a connection to the target host physical machine

    Figure 4.3. Adding a connection to the target host physical machine

    Enter the following details:
    • Hypervisor: Select QEMU/KVM.
    • Method: Select the connection method.
    • Username: Enter the user name for the remote host physical machine.
    • Hostname: Enter the host name for the remote host physical machine.
    Click the Connect button. An SSH connection is used in this example, so the specified user's password must be entered in the next step.
    Enter password

    Figure 4.4. Enter password

  4. Migrate guest virtual machines

    Open the list of guests inside the source host physical machine (click the small triangle on the left of the host name) and right click on the guest that is to be migrated (guest1-rhel6-64 in this example) and click Migrate.
    Choosing the guest to be migrated

    Figure 4.5. Choosing the guest to be migrated

    In the New Host field, use the drop-down list to select the host physical machine you wish to migrate the guest virtual machine to and click Migrate.
    Choosing the destination host physical machine and starting the migration process

    Figure 4.6. Choosing the destination host physical machine and starting the migration process

    A progress window will appear.
    Progress window

    Figure 4.7. Progress window

    virt-manager now displays the newly migrated guest virtual machine running in the destination host. The guest virtual machine that was running in the source host physical machine is now listed inthe Shutoff state.
    Migrated guest virtual machine running in the destination host physical machine

    Figure 4.8. Migrated guest virtual machine running in the destination host physical machine

  5. Optional - View the storage details for the host physical machine

    In the Edit menu, click Connection Details, the Connection Details window appears.
    Click the Storage tab. The iSCSI target details for the destination host physical machine is shown. Note that the migrated guest virtual machine is listed as using the storage
    Storage details

    Figure 4.9. Storage details

    This host was defined by the following XML configuration:
    
    <pool type='iscsi'>
        <name>iscsirhel6guest</name>
        <source>
            <host name='virtlab22.example.com.'/>
            <device path='iqn.2001-05.com.iscsivendor:0-8a0906-fbab74a06-a700000017a4cc89-rhevh'/>
        </source>
        <target>
            <path>/dev/disk/by-path</path>
        </target>
    </pool>
      ...

    Figure 4.10. XML configuration for the destination host physical machine