Solve the problem that the NIC cannot be identified by changing the mac address after copying ubuntu in virtualbox

After virtualbox is copied to ubuntu, the mac address cannot be identified. A ubuntu server 12.04 is installed in vbox, And the built-in replication function is used to build three virtual servers. In order to better simulate the LAN environment and ensure different mac addresses, refresh the mac address. When I log on to ifconfig, I find that eth0 is missing and naturally cannot connect to the network. Www.2cto.com finally found/etc/udev/rules. the d/70-persistent-net.rules file saves the mac address of the original VM Nic. At this time, the mac address is refreshed using vbox, which naturally cannot match, and ubuntu cannot identify the NIC. The solution is to delete the file and restart the virtual machine to use it.