sudo apt install virt-manager # includes libvirt/virsh/etc
curl -L https://vagrantup.com/whatever/vagrant-version.deb
sudo dpkg -i vagrant*.deb
For the vagrant-libvirt plugin you may need to use an alternate ruby/vagrant path in the call to install the plugin.
VIRSH_DEFAULT_CONNECT_URI The hypervisor to connect to by default. Set this to a URI , in the same format as accepted by the connect option. This environment variable is deprecated in favour of the global LIBVIRT_DEFAULT_URI variable which serves the same purpose. LIBVIRT_DEFAULT_URI The hypervisor to connect to by default. Set this to a URI , in the same format as accepted by the connect option. This overrides the default URI set in any client config file and prevents libvirt from probing for drivers.