今天在无线网络下，虚拟中的Ubuntu无法上网，解决方法如下，仅供参考：
无线网络下，Virtual Box设置2个网卡，网卡1：NAT、网卡2：Bridge 连接，vi /etc/network/interfaces
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
auto eth1
iface eth1 inet static
address 192.168.1.162 #设置eth1为静态ip，先查看主机ip地址，在同一网段设置此虚拟机ip
netmask 255.255.255.0
gateway 192.168.1.1
重启网络 /etc/init.d/networking restart
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1.如果是物理机是通过有线上网，那么需要使用NAT网络连接方式，如果是无线网络，那么需要使用桥接方式上网
对于桥接方式，需要把虚拟机的网关设置为物理机的网关：
1）vi /etc/network/interfaces
2）重启网络 /etc/init.d/networking restart
如果还是不行，比如ping www.baidu.com ，报：
ping: unknown host www.baidu.com
这时可以使用googl的公共DNScat /etc/resolv.conf
-------------------------------------------------------------------
nameserver 8.8.8.8
nameserver 8.8.4.4
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Ubuntu Network Error: Ignoring unknown interface eth0=eth0
When I ran "/sbin/ifup", or "/sbin/ifdown", or "/etc/init.d/networking restart", I got some error message like
Ignoring unknown interface eth0=eth0.
Ignoring unknown interface eth1=eth1.
Ignoring unknown interface eth2=eth2.
Ignoring unknown interface ath0=ath0.
Ignoring unknown interface wlan0=wlan0.
Note that I do have eth0, and "ifconfig" shows that it is up and has been assigned an IP.
To fix the error, check the file /etc/network/interfaces, comment out the unwanted interfaces, and keep at least the following:
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
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设置静态IP的方法
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
auto eth1
iface eth1 inet static
address 192.168.1.162 #设置eth1为静态ip
netmask 255.255.255.0
gateway 192.168.1.1
重启电脑