虚拟机与主机互ping不通，显示如下：
book@100ask:~$ ping 192.168.5.10
PING 192.168.5.10 (192.168.5.10) 56(84) bytes of data.
From 192.168.5.11 icmp_seq=1 Destination Host Unreachable
From 192.168.5.11 icmp_seq=2 Destination Host Unreachable
From 192.168.5.11 icmp_seq=3 Destination Host Unreachable
From 192.168.5.11 icmp_seq=4 Destination Host Unreachable
From 192.168.5.11 icmp_seq=5 Destination Host Unreachable
From 192.168.5.11 icmp_seq=6 Destination Host Unreachable
所有设置如下：
