eth0: ERROR while getting interface flags: No such device

出现这个问题有两种原因：

• 虚拟机设置中没有添加对应的网卡
• 更改了虚拟机中网卡的MAC，但是Debian 的缓存中将eth0与上次的MAC对应

解决方法：

这里仅就第二种问题提出解决方案：

删除/etc/udev/rules.d/70-persistent-net.rules，然后重新启动虚拟机。

参考：

http://askubuntu.com/questions/9375/new-mac-address-now-i-have-no-network-access

https://forums.virtualbox.org/viewtopic.php?f=7&t=43090

Since your mac address have changed you no longer have an interface called eth0, this name is reserved for an interface with the "old" mac-address. The "new" interface should have the next free name (eg. ethN).

each time you give a new MAC address (in VBox guest settings) Debian and Ubuntu guests udev assigns a new eth number
edit /etc/udev/rules.d/70-persistent-net.rules or delete the file: it will be recreated @ next boot