def METHOD_NAME(self):
    self.backing_chain = [self.base_tag]
    options = ["node", "overlay"]
    cmd = "blockdev-snapshot"
    arguments = self.params.copy_from_keys(options)
    for snapshot_tag in self.snapshot_chain:
        arguments["overlay"] = "drive_%s" % snapshot_tag
        self.main_vm.monitor.cmd(cmd, dict(arguments))
        arguments["node"] = "drive_%s" % snapshot_tag
        if snapshot_tag != self.snapshot_chain[-1]:
            self.backing_chain.append(snapshot_tag)
    self._top_device = "drive_%s" % self.snapshot_chain[-1]
    self.check_backing_chain()