'Create an insecure connection to the VM host.
The credentials for this connection only allow unverified
connections to the TLS endpoint of libvirtd.  The libvirtd
server must be configured to not verify the client credentials,
with server configuration ``tls_no_verify_certificate=1`` and
``tls_no_verify_address=1``.
This would be vulnerable to MITM attacks, but is used for
communication to the routing gateway (in particular from VM
guest to VM host), where a MITM attack is unlikely.
The tests require that disks are attached using libvirt, but not
using Cinder, as the problem they test is libvirt disks that are
not known by Cinder.  Note, this rules out solutions using
``mknod`` directly on the guest.
Creating a TLS connection is one of the simplest ways to set-up
libvirtd to listen on a network socket.  Disabling the actual
certificate verification on both ends of the connection allows
connection of the TLS endpoint without sharing any files (e.g.
CA cert and key, or a CSR).  This means the tests are contained
on one guest, with only a network connection required to attach
and delete nodes from the host.
:param instance_id: The UUID of the guest instance.
:param FilePath tempdir: A temporary directory that will exist
until the VirtIOClient is done.'

@classmethod
def using_insecure_tls(cls, instance_id, tempdir):

    url = 'qemu://{}/system?no_verify=1&pkipath={}'.format(cls._get_default_gateway(), tempdir.path)
    cls.create_credentials(tempdir)
    return cls(instance_id, url)
