grep ttyS0 /etc/securetty
#没有则加上
echo ttyS0 >> /etc/securetty
#启动
systemctl start serial-getty@ttyS0
systemctl enable serial-getty@ttyS0
systemctl start serial-getty@ttyS0
systemctl enable serial-getty@ttyS0
virsh console test-202
#或者
virsh console 51(序号)