After the CentOS virtual machine is cloned, Nic configuration problems CentOS Virtual Machine clone will conflict with the physical address, so the network adapter eth1 is automatically created and cannot start the network adapter. Solution: www.2cto.com Mode 1: 1) Modify/etc/sysconfig/network-scripts/ifcfg-eth0 to/etc/sysconfig/network-scripts/ifcfg-eth1 2) configure/etc/sysconfig/network-scripts/ifcfg-eth1 # change to eth1 DEVICE = "eth1" BOOTPROTO = "static" # hardware address from eth1 (obtained through ifconfig-) HWADDR = "00: 0C: 29: 91: 42: 2C "MTU =" 1500 "NM_CONTROLLED =" yes "ONBOOT =" yes "IPADDR = 192.168.152.101 NETMASK = 255.255.255.0 GATEWAY = 192.168.152.2 3) service network restart Mode 2: 1) modify/etc/udev/rules. d/70-persistent-net.rules copy the hardware address of eth1 to eth0 and delete eth1 Information 2) configure/etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE = "eth0" BOOTPROTO = "static" HWADDR = "00: 0C: 29: 91: 42: 2C "MTU =" 1500 "NM_CONTROLLED =" yes "ONBOOT =" yes "IPADDR = 192.168.152.101 NETMASK = 255.255.255.0 GATEWAY = 192.168.152.2 3) reboot Mode 3 (not tested): 1) delete/etc/udev/rules. d/70-persistent-net.rules 2) Configure/etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE = "eth0" BOOTPROTO = "static" HWADDR = "00: 0C: 29: 91: 42: 2C "MTU =" 1500 "NM_CONTROLLED =" yes "ONBOOT =" yes "IPADDR = 192.168.152.101 NETMASK = 255.255.255.0 GATEWAY = 192.168.152.2 3) reboot