[*virt-manager*](http://virt-manager.org/) is a Free Software virtualization solution for Linux. *virt-manager* has a more complex interface than *GNOME Boxes* but it also has a more complete set of features.
<p><i>virt-manager</i> is the only virtualization solution that allows to use a Persistent Storage. See [[running Tails from a USB image|virt-manager#usb_image]].</p>
*virt-manager* is based on a set of lower level virtualization tools, going from the user interface to the hardware interactions with the processor. This terminology is a bit confusing and other documentation might mention the following tools:
If you get the error message "<b>Error starting domain: Requested operation is not valid: network 'default' is not active</b>", then try to start the default virtual network:
<ol> <li>Click on <b>QEMU/KVM - Not Connected</b>.</li> <li>Choose <b>Edit ▸ Connection details</b> to administer the connection to your local <i>QEMU</i> system.</li> <li>Click on <b>Virtual Networks</b> tab, then select the <b>default</b> virtual network in the left pane.</li> <li>Click on the [[!img lib/media-playback-start.png alt="Start Network" link=no class=symbolic]] icon on the bottom of the left pane to start the default virtual network.</li> </ol>