To perform on-demand backup go to the Instances tab under the Virtual Environment section.
You can click on icon to backup one VM
Finally select a backup type, backup destination, when a task should start, priority, and click on the backup button.
On the Tasks Console, you can see the progress of the backup task.
Or select multiple virtual machines and click on icon to backup them.
Note: You can also perform the same action thanks to the CLI interface: