6.13. Migrating Virtual Machines Between Hosts

Procedure 6.28. Configuring Auto-convergence and Migration Compression for Virtual Machine Migration

1. Configure the optimization settings at the global level:
   1. Enable auto-convergence at the global level:

      # engine-config -s DefaultAutoConvergence=True

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   2. Enable migration compression at the global level:

      # engine-config -s DefaultMigrationCompression=True

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   3. Restart the ovirt-engine service to apply the changes:

      # systemctl restart ovirt-engine.service

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2. Configure the optimization settings at the cluster level:
   1. Select a cluster.
   2. Click Edit.
   3. Click the Migration Policy tab.
   4. From the Auto Converge migrations list, select Inherit from global setting, Auto Converge, or Don't Auto Converge.
   5. From the Enable migration compression list, select Inherit from global setting, Compress, or Don't Compress.
3. Configure the optimization settings at the virtual machine level:
   1. Select a virtual machine.
   2. Click Edit.
   3. Click the Host tab.
   4. From the Auto Converge migrations list, select Inherit from cluster setting, Auto Converge, or Don't Auto Converge.
   5. From the Enable migration compression list, select Inherit from cluster setting, Compress, or Don't Compress.

Procedure 6.29. Preventing Automatic Migration of Virtual Machine

1. Click the Virtual Machines tab and select a virtual machine.
2. Click Edit.
   

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   Figure 6.19. The Edit Virtual Machine Window

3. Click the Host tab.
4. Use the Start Running On radio buttons to designate the virtual machine to run on Any Host in Cluster or a Specific host. If applicable, select a specific host or group of hosts from the list.

   Warning

   Explicitly assigning a virtual machine to one specific host and disabling migration is mutually exclusive with Red Hat Virtualization high availability. Virtual machines that are assigned to one specific host can only be made highly available using third party high availability products like Red Hat High Availability. This restriction does not apply to virtual machines that are assigned to multiple specific hosts.

   Important

   If the virtual machine has host devices directly attached to it, and a different host is specified, the host devices from the previous host will be automatically removed from the virtual machine.
5. Select Allow manual migration only or Do not allow migration from the Migration Options drop-down list.
6. Optionally, select the Use custom migration downtime check box and specify a value in milliseconds.
7. Click OK.

Procedure 6.30. Manually Migrating Virtual Machines

1. Click the Virtual Machines tab and select a running virtual machine.
2. Click Migrate.
3. Use the radio buttons to select whether to Select Host Automatically or to Select Destination Host, specifying the host using the drop-down list.

   Note

   When the Select Host Automatically option is selected, the system determines the host to which the virtual machine is migrated according to the load balancing and power management rules set up in the scheduling policy.
4. Click OK.

Procedure 6.31. Setting Migration Priority

1. Click the Virtual Machines tab and select a virtual machine.
2. Click Edit.
3. Select the High Availability tab.
4. Select Low, Medium, or High from the Priority drop-down list.
5. Click OK.

Procedure 6.32. Canceling Ongoing Virtual Machine Migrations

1. Select the migrating virtual machine. It is displayed in the Virtual Machines resource tab with a status of Migrating from.
2. Click Cancel Migration.