Virt-Manager is a desktop user interface for managing virtual machines, primarily focused on KVM/QEMU virtual machines, but can also manage XEN and LXC Linux container virtual machines.

It provides a summary of running domains, their real-time performance, and resource usage statistics. Wizards allow you to create new domains, as well as configure and adjust domain resource allocation and virtual hardware. A built-in VNC and SPICE client provides a fully functional graphical console for guest domains.

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RemoteBox is a graphical utility that allows you to administer virtual machines running in VirtualBox over a network, either on a remote server or on a local machine. This allows you to remotely administer a server running VirtualBox and interact with the virtual machines as if they were running locally.

VirtualBox is installed on the "server" machine, and RemoteBox runs on the "client" machine. RemoteBox provides a full GTK graphical interface with a look and feel very similar to the built-in VirtualBox GUI.