kvm to vbox network settting： No

1. 镜像转换

qemu-img convert -O vdi gnome.qcow2 gnome.vdi

#if its a raw image then:
VBoxManage convertdd opnstk.raw VBox.vdi --format VDI

2. 导入后网络问题 No suitable device found for this connection.
   原因是导入后的网卡地址发生了改变，
   复制一份 之前的网络配置，修改里面的 HWADDR="08:00:27:0c:f8:08" 修改成新的网站地址
   重启即可

$ ssh root@192.168.3.155
Last login: Tue Nov 27 15:08:02 2018
[root@cbmdev ~]# ps aux | grep -i network
root       670  0.1  0.4 552172  9188 ?        Ssl  15:07   0:00 /usr/sbin/NetworkManager --no-daemon
root       723  0.0  0.2 107396  5480 ?        S    15:07   0:00 /sbin/dhclient -d -q -sf /usr/libexec/nm-dhcp-helper -pf /var/run/dhclient-enp0s3.pid -lf /var/lib/NetworkManager/dhclient-a0055547-c330-38d0-acde-72bff2d7cb53-enp0s3.lease -cf /var/lib/NetworkManager/dhclient-enp0s3.conf enp0s3
root      1232  0.0  0.0 112704   988 pts/0    S+   15:11   0:00 grep --color -a --exclude-dir=braintree --exclude-dir=.svn --exclude-dir=node_modules --exclude=*.gif --exclude=*.png --exclude=*.psd --exclude=*.jpg --exclude=*.min.js --exclude-dir=.git --exclude-dir=logs --exclude-dir=vendor -i network
[root@cbmdev ~]# nmcli connection show
NAME                UUID                                  TYPE      DEVICE
Wired connection 1  a0055547-c330-38d0-acde-72bff2d7cb53  ethernet  enp0s3
ens3                0a32cbf0-2aaa-4efa-97f2-114a89d2f16e  ethernet  --
[root@cbmdev ~]# nmcli connection show -a
NAME                UUID                                  TYPE      DEVICE
Wired connection 1  a0055547-c330-38d0-acde-72bff2d7cb53  ethernet  enp0s3
[root@cbmdev ~]#
[root@cbmdev ~]#
[root@cbmdev ~]# nmcli device status
DEVICE  TYPE      STATE      CONNECTION
enp0s3  ethernet  connected  Wired connection 1
lo      loopback  unmanaged  --
[root@cbmdev ~]# nmcli device connect ens3
Error: Device 'ens3' not found.
[root@cbmdev ~]# systemctl status network.service
● network.service - LSB: Bring up/down networking
   Loaded: loaded (/etc/rc.d/init.d/network; bad; vendor preset: disabled)
   Active: inactive (dead)
     Docs: man:systemd-sysv-generator(8)
[root@cbmdev ~]# systemctl start network.service
Job for network.service failed because the control process exited with error code. See "systemctl status network.service" and "journalctl -xe" for details.
[root@cbmdev ~]# systemctl status network.service
● network.service - LSB: Bring up/down networking
   Loaded: loaded (/etc/rc.d/init.d/network; bad; vendor preset: disabled)
   Active: failed (Result: exit-code) since Tue 2018-11-27 15:14:39 CST; 9s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 1261 ExecStart=/etc/rc.d/init.d/network start (code=exited, status=1/FAILURE)

Nov 27 15:14:38 cbmdev systemd[1]: Starting LSB: Bring up/down networking...
Nov 27 15:14:39 cbmdev network[1261]: Bringing up loopback interface:  [  OK  ]
Nov 27 15:14:39 cbmdev network[1261]: Bringing up interface ens3:  Error: Connection activation failed: No suitable device found for this connection.
Nov 27 15:14:39 cbmdev network[1261]: [FAILED]
Nov 27 15:14:39 cbmdev systemd[1]: network.service: control process exited, code=exited status=1
Nov 27 15:14:39 cbmdev systemd[1]: Failed to start LSB: Bring up/down networking.
Nov 27 15:14:39 cbmdev systemd[1]: Unit network.service entered failed state.
Nov 27 15:14:39 cbmdev systemd[1]: network.service failed.
[root@cbmdev ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 08:00:27:0c:f8:08 brd ff:ff:ff:ff:ff:ff
    inet 192.168.3.155/22 brd 192.168.3.255 scope global noprefixroute dynamic enp0s3
       valid_lft 89509sec preferred_lft 89509sec
    inet6 fe80::591a:c5fc:e79:60ca/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
[root@cbmdev ~]# cd /etc/sysconfig/network-scripts/
[root@cbmdev network-scripts]# cp ifcfg-ens3 ifcfg-enp0s3
[root@cbmdev network-scripts]# vim ifcfg-enp0s3

[root@cbmdev ~]# cat /etc/sysconfig/network-scripts/ifcfg-enp0s3
TYPE="Ethernet"
PROXY_METHOD="none"
BROWSER_ONLY="no"
BOOTPROTO="static"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="enp0s3"
HWADDR="08:00:27:0c:f8:08"
UUID="0a32cbf0-2aaa-4efa-97f2-114a89d2f16e"
DEVICE="enp0s3"
ONBOOT="yes"
HWADDR="08:00:27:0c:f8:08"
IPADDR=192.168.0.234
GATEWAY=192.168.0.1
NETMASK=255.255.0.0
DNS1=192.168.0.10
DNS2=114.114.114.114