在centos 6 环境下KVM的安装部分，我写过kvm虚拟化小结（一）kvm环境安装 。由于centos 7较之前的版本有了很大的变化，目前测试了centos 7 环境下kvm的安装与搭建，具体如下。

一、安装kvm 软件

由于之前已做过较详细的 kvm 的安装与总结，这里只大致列下步骤：

 代码如下 复制代码
[root@itnetcn ~]# yum -y install qemu-kvm libvirt virt-install bridge-utils
 [root@itnetcn ~]# lsmod | grep kvm  # make sure modules are loaded
 kvm                   441119  0
 [root@itnetcn ~]# systemctl start libvirtd
 [root@itnetcn ~]# systemctl enable libvirtd
 

注：centos7上服务的管理方式换成了systemctl 。

二、配置网卡桥接

centos7上默认已不再是eth0、eth1 ，我的pc server上安装好的第一块网卡变成了enp3s0 ，修改步骤和centos 6上没有区别，如下
 

 代码如下 复制代码
[root@itnetcn ~]# cd /etc/sysconfig/network-scripts/
 [root@itnetcn network-scripts]# cat ifcfg-br0
 TYPE=Bridge
 BOOTPROTO=none
 DEVICE=br0
 ONBOOT=yes
 IPADDR0=192.168.0.102
 PREFIX0=24
 GATEWAY0=192.168.0.1
 [root@itnetcn network-scripts]# cat ifcfg-enp3s0
 DEVICE=enp3s0
 TYPE=Ethernet
 ONBOOT=yes
 BRIDGE=br0
 [root@itnetcn ~]reboot
 [root@itnetcn network-scripts]# ifconfig
 br0: flags=4163  mtu 1500
         inet 192.168.0.102  netmask 255.255.255.0  broadcast 192.168.0.255
         inet6 fe80::7a24:afff:fe46:ca60  prefixlen 64  scopeid 0x20
         ether 78:24:af:46:ca:60  txqueuelen 0  (Ethernet)
         RX packets 129  bytes 14676 (14.3 KiB)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 148  bytes 21994 (21.4 KiB)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
 enp3s0: flags=4163  mtu 1500
         ether 78:24:af:46:ca:60  txqueuelen 1000  (Ethernet)
         RX packets 129  bytes 16482 (16.0 KiB)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 148  bytes 21994 (21.4 KiB)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
 lo: flags=73  mtu 65536
         inet 127.0.0.1  netmask 255.0.0.0
         inet6 ::(www.it.net.cn)1  prefixlen 128  scopeid 0x10
         loop  txqueuelen 0  (Local Loopback)
         RX packets 9  bytes 728 (728.0 B)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 9  bytes 728 (728.0 B)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
 virbr0: flags=4099  mtu 1500
         inet 192.168.122.1  netmask 255.255.255.0  broadcast 192.168.122.255
         ether a6:88:9f:14:b2:66  txqueuelen 0  (Ethernet)
         RX packets 0  bytes 0 (0.0 B)
         RX errors 0  dropped 0  overruns 0  frame 0
         TX packets 1  bytes 90 (90.0 B)
         TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0


 [root@itnetcn network-scripts]# ip add show


 1: lo:  mtu 65536 qdisc noqueue state UNKNOWN
     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: enp3s0:  mtu 1500 qdisc pfifo_fast master br0 state UP qlen 1000
     link/ether 78:24:af:46:ca:60 brd ff:ff:ff:ff:ff:ff


 3: br0:  mtu 1500 qdisc noqueue state UP

     link/ether 78:24:af:46:ca:60 brd ff:ff:ff:ff:ff:ff
     inet 192.168.0.102/24 brd 192.168.0.255 scope global br0
        valid_lft forever preferred_lft forever
     inet6 fe80::7a24:afff:fe46:ca60/64 scope link
        valid_lft forever preferred_lft forever


 4: virbr0:  mtu 1500 qdisc noqueue state DOWN
     link/ether a6:88:9f:14:b2:66 brd ff:ff:ff:ff:ff:ff
     inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
        valid_lft forever preferred_lft forever
 

注：由于ip 命令属于iproute2软件包中的工具，由于代替旧的ifconfig命令，尽可能的习惯使用新的命令和工具包来淘汰老的软件和工具。

三、selinux防火墙关闭

 代码如下 复制代码

# setenforce  0
 # sed -i 's/=enforcing/=disabled/g' /etc/selinux/config