首先在虚拟机管理界面中给该虚拟机添加一块虚拟网卡，VirtualBox虚拟机中要shutdown才能添加。

[root@rhel7 ~]# nmcli device show | grep -i device   --查看网卡设备，我们可以看到新添加的enp0s8GENERAL.DEVICE:                         virbr0GENERAL.DEVICE:                         enp0s3GENERAL.DEVICE:                         virbr0-nicGENERAL.DEVICE:                         enp0s8GENERAL.DEVICE:                         lo[root@rhel7 ~]# nmcli connection show     ---还得添加网卡配置文件才能查看到enp0s8NAME        UUID                                  TYPE            DEVICE     virbr0-nic  c6a02e0f-24af-4b3b-983d-1643fee355df  generic         virbr0-nic virbr0      eecfd3a6-4d29-4f9c-a62c-1a30df56e011  bridge          virbr0     enp0s3      df34c879-c2bd-4c82-ae7a-39e39a2228dd  802-3-ethernet  enp0s3

添加enp0s8的网卡配置文件：

[root@rhel7 ~]# nmcli connection add type ethernet con-name enp0s8 ifname enp0s8 autoconnect yesConnection 'enp0s8' (8bf108aa-9c89-4c2c-a5d3-3d9346b2c644) successfully added.[root@rhel7 ~]# nmcli connection showNAME        UUID                                  TYPE            DEVICE     virbr0-nic  c6a02e0f-24af-4b3b-983d-1643fee355df  generic         virbr0-nic virbr0      eecfd3a6-4d29-4f9c-a62c-1a30df56e011  bridge          virbr0     enp0s3      df34c879-c2bd-4c82-ae7a-39e39a2228dd  802-3-ethernet  enp0s3     enp0s8      8bf108aa-9c89-4c2c-a5d3-3d9346b2c644  802-3-ethernet  enp0s8

配置IP地址及其它信息：

[root@rhel7 ~]# nmcli connection modify enp0s8  ipv4.addresses 192.168.1.200/24 ipv4.gateway 192.168.1.99  ipv4.dns 192.168.1.1 ipv4.method manual connection.autoconnect yes

启动enp0s8网卡：

[root@rhel7 ~]# nmcli connection up enp0s8Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/13)[root@rhel7 ~]# ip a s enp0s83: enp0s8: 
     
       mtu 1500 qdisc pfifo_fast state UP qlen 1000    link/ether 08:00:27:79:3c:2c brd ff:ff:ff:ff:ff:ff    inet 192.168.1.200/24 brd 192.168.1.255 scope global enp0s8       valid_lft forever preferred_lft forever    inet6 fe80::a00:27ff:fe79:3c2c/64 scope link        valid_lft forever preferred_lft forever
     

网卡添加配置完成。

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给enp0s8再配置一个IP地址192.168.1.201：

[root@rhel7 ~]# nmcli connection modify enp0s8 +ipv4.addresses 192.168.1.201/24 ipv4.gateway 192.168.1.99[root@rhel7 ~]# nmcli connection down enp0s8   --重启网卡Connection 'enp0s8' successfully deactivated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/13)[root@rhel7 ~]# nmcli connection up enp0s8Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/14)[root@rhel7 ~]# nmcli connection show NAME        UUID                                  TYPE            DEVICE     virbr0-nic  c6a02e0f-24af-4b3b-983d-1643fee355df  generic         virbr0-nic virbr0      eecfd3a6-4d29-4f9c-a62c-1a30df56e011  bridge          virbr0     enp0s3      df34c879-c2bd-4c82-ae7a-39e39a2228dd  802-3-ethernet  enp0s3     enp0s8      8bf108aa-9c89-4c2c-a5d3-3d9346b2c644  802-3-ethernet  enp0s8     [root@rhel7 ~]# ip addr show enp0s8 --查看添加成功3: enp0s8: 
     
       mtu 1500 qdisc pfifo_fast state UP qlen 1000    link/ether 08:00:27:79:3c:2c brd ff:ff:ff:ff:ff:ff    inet 192.168.1.200/24 brd 192.168.1.255 scope global enp0s8       valid_lft forever preferred_lft forever    inet 192.168.1.201/24 brd 192.168.1.255 scope global secondary enp0s8       valid_lft forever preferred_lft forever    inet6 fe80::a00:27ff:fe79:3c2c/64 scope link        valid_lft forever preferred_lft forever[root@rhel7 ~]#
     

 给enp0s8再配置一个IPv6地址2001::1/64

[root@rhel7 ~]# nmcli connection modify enp0s8  ipv6.method manual ipv6.addresses 2001::1/64  ipv6.gateway 2001::1 ipv6.dns 2001::1[root@rhel7 ~]# ping6 2001::1connect: Network is unreachable[root@rhel7 ~]# nmcli connection down enp0s8Connection 'enp0s8' successfully deactivated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/14)[root@rhel7 ~]# nmcli connection up enp0s8Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/15)[root@rhel7 ~]# ping6 2001::1PING 2001::1(2001::1) 56 data bytes64 bytes from 2001::1: icmp_seq=1 ttl=64 time=0.062 ms64 bytes from 2001::1: icmp_seq=2 ttl=64 time=0.116 ms64 bytes from 2001::1: icmp_seq=3 ttl=64 time=0.119 ms^C--- 2001::1 ping statistics ---3 packets transmitted, 3 received, 0% packet loss, time 2000msrtt min/avg/max/mdev = 0.062/0.099/0.119/0.026 ms[root@rhel7 ~]#