CentOS7上安装并使用KVM

CentOS7上安装并配置KVM，以及通过KVM安装CentOS系统

1. ssh免密码

ssh-copy-id -i ~/.ssh/id_rsa.pub  root@192.168.0.2

2. 修改静态IP地址

vim /etc/sysconfig/network-scripts/ifcfg-enp0s25

BOOTPROTO=static
ONBOOT=yes
IPADDR=192.168.0.2
NETMASK=255.255.255.0
GATEWAY=192.168.0.1

3. 停止防火墙

systemctl stop firewalld
systemctl disable firewalld

4. 停止selinux

setenforce 0

vim /etc/selinux/config
SELINUX=disabled

5. 安装常用工具

yum install git vim net-tools wget

6. 安装KVM

yum install -y  virt-*  libvirt  bridge-utils qemu-img

7. 配置网桥

cd /etc/sysconfig/network-scripts/

[root@localhost network-scripts]# cd /etc/sysconfig/network-scripts/
[root@localhost network-scripts]# cat ifcfg-enp0s25
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=enp0s25
UUID=2d353bf4-691e-44a9-b6e2-0e6c1d9fc082
DEVICE=enp0s25
ONBOOT=yes
IPADDR=192.168.0.2
NETMASK=255.255.255.0
GATEWAY=192.168.0.1
BRIDGE=br0
[root@localhost network-scripts]# cat ifcfg-br0
NAME="br0"
DEVICE="br0"
TYPE=Bridge
ONBOOT=yes
IPADDR=192.168.0.2
NETMASK=255.255.255.0
GATEWAY=192.168.0.1
BOOTPROTO=static

[root@localhost network-scripts]# systemctl restart network

启动KVM服务

[root@localhost ~]# lsmod |grep kvm  # 检查KVM模块是否加载
kvm_intel             162153  0 
kvm                   525259  1 kvm_intel
[root@localhost ~]# systemctl start libvirtd  # 启动libvirtd服务
[root@localhost ~]# ps aux |grep libvirtd  # 检查服务进程
root       5744  2.2  0.1 614840 14120 ?        Ssl  23:02   0:00 /usr/sbin/libvirtd
root       5872  0.0  0.0 112664   964 pts/1    R+   23:02   0:00 grep --color=auto libvirtd
[root@localhost ~]# brctl show  # 可以看到两个网卡
bridge name bridge id       STP enabled interfaces
br0     8000.000c29f1912c   no      eno16777728  # 我们配置的桥接网卡
virbr0      8000.525400240b50   yes     virbr0-nic  # NAT模式的网卡
[root@localhost ~]# 

创建虚拟机安装CentOS7

[root@localhost ~]# virt-install --name=study01 --memory=512,maxmemory=1024 --vcpus=1,maxvcpus=2 --os-type=linux --os-variant=rhel7 --location=/kvm/iso/CentOS-7-x86_64-Minimal-1810.iso --disk path=/kvm/disk/study01.img,size=10 --bridge=br0 --graphics=none --console=pty,target_type=serial  --extra-args="console=tty0 console=ttyS0"

虚拟机管理

[root@localhost ~]# virsh list
[root@localhost ~]# virsh list --all
[root@localhost ~]# ls /etc/libvirt/qemu/
networks  study01.xml
[root@localhost ~]# ls /etc/libvirt/qemu/networks/
autostart  default.xml
[root@localhost ~]# ls /etc/libvirt/qemu/networks/autostart/
default.xml
[root@localhost ~]# 

[root@localhost ~]# virsh console study01  # 进入指定的虚拟机，进入的时候还需要按一下回车
[root@localhost ~]# virsh start study01  # 启动虚拟机
[root@localhost ~]# virsh shutdown study01  # 关闭虚拟机
[root@localhost ~]# virsh destroy study01  # 强制停止虚拟机
[root@localhost ~]# virsh undefine study01  # 彻底销毁虚拟机，会删除虚拟机配置文件，但不会删除虚拟磁盘
[root@localhost ~]# virsh autostart study01  # 设置宿主机开机时该虚拟机也开机
[root@localhost ~]# virsh autostart --disable study01  # 解除开机启动
[root@localhost ~]# virsh suspend study01 # 挂起虚拟机
[root@localhost ~]# virsh resume study01 # 恢复挂起的虚拟机

参考：https://blog.51cto.com/zero01/2083896