CentOS7安装配置KVM

一、安装kvm

1、安装libvirt软件包

# 必装包
shell> yum -y install libcanberra-gtk2 qemu-kvm.x86_64 qemu-kvm-tools.x86_64 \
libvirt.x86_64 libvirt-cim.x86_64 libvirt-client.x86_64 libvirt-java.noarch  libvirt-python.x86_64 \
dbus-devel virt-clone virt-manager libvirt libvirt-python virt-viewer \
libiscsi-1.7.0-5.el6.x86_64 tunctl python-virtinst

# 选装包：增加virt-edit、virt-copy-in命令支持
shell> yum -y install libguestfs-tools-c.x86_64

# CentOS7.5默认kernel有bug，在CentOS5.8 32bit虚机里执行重启操作，会导致宿主机崩溃，需要升级kernel解决。
shell> yum -y update kernel

2、启动libvirt

shell> systemctl start libvirtd
shell> systemctl enable libvirtd

3、修改libvirt vm镜像默认位置

shell> mkdir /export/kvm_images/
shell> cat >> /export/default.xml << EOF
<pool type='dir'>
  <name>default</name>
  <source> 
  </source>
  <target>
    <path>/export/kvm_images</path>
    <permissions>
      <mode>0755</mode>
      <owner>0</owner>
      <group>0</group>
    </permissions>
  </target>
</pool>
EOF

shell> virsh pool-define /export/default.xml
shell> virsh pool-autostart default
shell> virsh pool-start default

4、libvirtd部分配置项优化

• 查看启动配置

shell> cat /usr/lib/systemd/system/libvirtd.service
# 确认是否有如下信息
EnvironmentFile=-/etc/sysconfig/libvirtd

• 修改qemu-kvm默认监听地址，开放远程连接权限

shell> sed -i 's/#vnc_listen.*/vnc_listen = "0.0.0.0"/' /etc/libvirt/qemu.conf 

• 编辑启动配置，载入环境配置文件

shell> vi /etc/sysconfig/libvirtd
    LIBVIRTD_CONFIG=/etc/libvirt/libvirtd.conf
    LIBVIRTD_ARGS="--listen"

• 编辑环境配置文件，启用tcp和sasl加密

shell> vi /etc/libvirt/libvirtd.conf
    listen_tls = 0
    listen_tcp = 1
    tcp_port = "16509"
    listen_addr = "0.0.0.0"
    auth_tcp = "sasl"

• 编辑sasl加密配置，使用md5加密

shell> vi /etc/sasl2/libvirt.conf
    mech_list: digest-md5
    sasldb_path: /etc/libvirt/passwd.db

• 安装sasl-md5加密支持

shell> yum -y install cyrus-sasl-md5

• 创建 kvm_user 用户，用于tcp连接

# 设置密码: ******
shell> saslpasswd2 -a libvirt kvm_user 

• 重启libvirtd进程，开启tcp连接。

shell> systemctl restart libvirtd

三、设置网卡桥接bridge模式

1、修改eth0网卡

shell> vi /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
TYPE=Ethernet
ONBOOT=yes
BOOTPROTO=static
BRIDGE=br0

2、创建br0网卡

shell> vi /etc/sysconfig/network-scripts/ifcfg-br0
DEVICE=br0
TYPE=Bridge
ONBOOT=yes
BOOTPROTO=static
IPADDR=59.151.49.104
PREFIX=24
GATEWAY=59.151.49.1

四、修改主机名

shell> hostnamectl --static set-hostname xg-kvm-201234