KVM进阶使用
**作者：行癫（盗版必究）**
------
## 一：KVM克隆
#### 1.图形化管理方式
关闭要克隆的虚拟机，右键点击虚拟机选择Clone
#### 2.字符终端
```shell
[root@localhost ~]# virt-clone -o centos7.0 -n xingdian -f /var/lib/libvirt/images/xingdian.qcow2
Allocating 'xingdian.qcow2' | 10 GB 00:00:03
Clone 'xingdian' created successfully.
注意：
-o：需要克隆的虚拟机名字
-n：克隆后虚拟机的名字
-f：指定克隆后的镜像文件
```
验证：
## 二：KVM网络
#### 1.NAT网络拓扑
注意：
默认情况下使用的就是NAT网络模式
#### 2.桥接网络拓扑
#### 3.网络相关基本命令
查看一个guest主机的网络接口信息：
```shell
[root@localhost ~]# virsh domiflist xingdian
Interface Type Source Model MAC
-------------------------------------------------------
- network default virtio 52:54:00:89:aa:71
```
列出运行网络信息：
```shell
[root@localhost ~]# virsh net-list
Name State Autostart Persistent
----------------------------------------------------------
default active yes yes
```
列出网络详细信息：
```shell
[root@localhost ~]# virsh net-info default
Name: default
UUID: cdea1242-f581-4624-86d7-c52629b52774
Active: yes
Persistent: yes
Autostart: yes
Bridge: virbr0
```
导出默认网络信息：
```shell
[root@localhost ~]# virsh net-dumpxml default > default.xml
[root@localhost ~]# cat default.xml
default
cdea1242-f581-4624-86d7-c52629b52774
```
生成网络xml文件：
```shell
[root@localhost ~]# cp default.xml xingdian.xml
[root@localhost ~]# cat xingdian.xml
xingdian
cdea1242-f581-4624-86d7-c52629b52794
```
利用xml生成新的文件：
```shell
[root@localhost ~]# virsh net-create xingdian.xml
Network xingdian created from xingdian.xml
```
开启持久化网络：
```shell
[root@localhost ~]# virsh net-define xingdian.xml //利用xml文件开启
Network xingdian defined from xingdian.xml
[root@localhost ~]# virsh net-list
Name State Autostart Persistent
----------------------------------------------------------
default active yes yes
diandian active yes yes
xingdian active no yes
```
取消持久化网络：
```shell
[root@localhost ~]# virsh net-undefine xingdian
Network xingdian has been undefined
[root@localhost ~]# virsh net-list
Name State Autostart Persistent
----------------------------------------------------------
default active yes yes
diandian active yes yes
xingdian active no no
```
自启动网络：
```shell
[root@localhost ~]# virsh net-autostart --disable diandian
Network diandian unmarked as autostarted
[root@localhost ~]# virsh net-list --all
Name State Autostart Persistent
----------------------------------------------------------
default active yes yes
diandian active no yes
xingdian active no no
[root@localhost ~]# virsh net-autostart --network diandian
Network diandian marked as autostarted
[root@localhost ~]# virsh net-list --all
Name State Autostart Persistent
----------------------------------------------------------
default active yes yes
diandian active yes yes
xingdian active no no
```
查看虚拟机IP地址：
```shell
[root@localhost ~]# virsh dumpxml xingdian | grep mac
/machine
hvm
[root@localhost ~]# arp -a | grep 52:54:00:89:aa:71
? (192.168.122.54) at 52:54:00:89:aa:71 [ether] on virbr0
```
#### 4.创建桥接网络
创建桥接网卡br0，把br0作为网桥使用，绑定enp2s0到br0网桥：
```shell
[root@localhost ~]# virsh iface-bridge ens33 br0
```
执行上述命令，实际上就是在/etc/sysconfig/networking-script目录下增加一个虚拟网桥 br0,文件名称为ifcfg-br0
```shell
[root@localhost network-scripts]# cat ifcfg-br0
DEVICE="br0"
ONBOOT="yes"
TYPE="Bridge"
BOOTPROTO="dhcp"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
DHCPV6C="no"
STP="on"
DELAY="0"
```
查看网卡配置文件
```shell
[root@localhost network-scripts]# cat ifcfg-ens33
DEVICE="ens33"
ONBOOT="yes"
BRIDGE="br0"
```
重启网络：
```shell
[root@localhost network-scripts]# systemctl restart network
```
查看桥接：
```shell
[root@localhost network-scripts]# brctl show
bridge name bridge id STP enabled interfaces
br0 8000.000c29f4ba45 yes ens33
vnet1
virbr0 8000.5254001080ce yes virbr0-nic
vnet0
virbr1 8000.5254001081ce yes virbr1-nic
virbr2 8000.525400035e3c yes virbr2-nic
```
使用桥接：
## 三：KVM快照
#### 1.图形化方式
#### 2.命令方式
为虚拟机创建快照：
```shell
[root@localhost ~]# virsh snapshot-create-as xingdian xingdian.snap
Domain snapshot xingdian.snap created
```
查看镜像信息：
```shell
[root@localhost ~]# qemu-img info /var/lib/libvirt/images/xingdian.qcow2
image: /var/lib/libvirt/images/xingdian.qcow2
file format: qcow2
virtual size: 10G (10737418240 bytes)
disk size: 1.5G
cluster_size: 65536
Snapshot list:
ID TAG VM SIZE DATE VM CLOCK
1 xingdian.snap 248M 2022-07-12 01:16:13 00:40:55.839
Format specific information:
compat: 1.1
lazy refcounts: true
```
虚拟机增加内容，创建快照：
```shell
[root@localhost ~]# touch a.txt
[root@localhost ~]# virsh snapshot-create-as xingdian xingdian.snap2
Domain snapshot xingdian.snap2 created
```
关闭虚拟机，恢复到第一个快照：
```shell
[root@localhost ~]# virsh shutdown xingdian
Domain xingdian is being shutdown
[root@localhost ~]# virsh snapshot-revert xingdian xingdian.snap
```
验证：
```shell
[root@localhost ~]# virsh list
Id Name State
----------------------------------------------------
6 xingdian running
[root@localhost ~]# ssh 192.168.122.54
root@192.168.122.54's password:
Last login: Tue Jul 12 00:56:36 2022 from 192.168.122.1
[root@localhost ~]# ls
anaconda-ks.cfg
```
注意：
没有a.txt代表恢复快照成功
## 四：脚本管理KVM
```shell
[root@localhost ~]# cat kvm-manager.sh
#!/bin/bash
#kvm manager
#by xingdian.
#for centos7
images_dir=/var/lib/libvirt/images
xml_dir=/etc/libvirt/qemu
red_col="\e[1;31m"
blue_col="\e[1;34m"
reset_col="\e[0m"
centos6u8_base_img=centos6u8_base.qcow2
centos7u3_base_img=centos7u3_base.qcow2
win7_base_img=win7_base.qcow2
centos6u8_base_xml=centos6u8_base.xml
centos7u3_base_xml=centos7u3_base.xml
win7_base_xml=win7_base.xml
menu() {
cat <<-EOF
+------------------------------------------------+
| |
| ====================== |
| 虚拟机基本管理 v4.0 |
| by xingdian |
| ====================== |
| 1. 安装KVM |
| 2. 安装或重置CentOS-6.8 |
| 3. 安装或重置CentOS-7.3 |
| 4. 安装或重置Windows-7 |
| 5. 删除所有虚拟机 |
| q. 退出管理程序 |
| |
+------------------------------------------------+
EOF
}
kvm_install_hint() {
systemctl libvirtd status &>/dev/null
if [ $? -ne 0 ];then
echo -e "${red_col}未安装KVM软件或未启动libvirtd进程，请检查${reset_col}"
continue
fi
}
download_kvm_script() {
wget -O /root/Desktop/virt-manager.desktop ftp://10.18.40.100/kvm/virt-manager.desktop &>/dev/null
wget -O /root/Desktop/Readme.txt ftp://10.18.40.100/kvm/readme.txt &>/dev/null
chmod a+x /root/Desktop/virt-manager.desktop &>/dev/null
wget -O /root/桌面/virt-manager.desktop ftp://10.18.40.100/virt-manager.desktop &>/dev/null
wget -O /root/桌面/Readme.txt ftp://10.18.40.100/kvm/readme.txt &>/dev/null
chmod a+x /root/桌面/virt-manager.desktop &>/dev/null
wget -O /usr/local/sbin/kvm-manager ftp://10.18.40.100/kvm/kvm-manager.sh &>/dev/null
chmod a+x /usr/local/sbin/kvm-manager &>/dev/null
}
conn_test() {
ping -c1 10.18.40.100 &>/dev/null
if [ $? -ne 0 ];then
echo -e "${red_col}无法访问10.18.40.100, 请检查网络或稍后再试!${reset_col}"
echo
exit
fi
}
menu
while :
do
echo -en "${blue_col}请选择相应的操作[1-7], 显示菜单[m]: ${reset_col}"
read choose
case $choose in
1)
conn_test
download_kvm_script
read -p "确认开始安装KVM [y]: " kvm_install
if [ ! "${kvm_install}" = "y" ];then
echo -e "$red_col输入不正确! $reset_col"
continue
fi
rpm -q virt-manager &>/dev/null
if [ $? -ne 0 ];then
echo "开始安装KVM......"
yum -y groupinstall "virtual*"
systemctl start libvirtd
systemctl enable libvirtd
fi
echo "-----------------------------------------------------------"
echo "KVM 安装完成，请查看桌面上的Readme文件..."
echo "-----------------------------------------------------------"
;;
2)
conn_test
download_kvm_script
read -p "确认重置CentOS 6.8 虚拟机吗?[y]: " rebuild_centos6u8
if [ ! "${rebuild_centos6u8}" = "y" ];then
echo -e "$red_col输入不正确! $reset_col"
continue
fi
if [ ! -f ${images_dir}/${centos6u8_base_img} ];then
echo "正在下载镜像文件，请稍候......"
wget -O ${images_dir}/${centos6u8_base_img} ftp://10.18.40.100/kvm/base_image/${centos6u8_base_img}
fi
for i in {1..5}
do
vm_name=centos6u8-${i}
vm_uuid=$(uuidgen)
vm_disk=${vm_name}.qcow2
vm_xml=${xml_dir}/${vm_name}.xml
vm_mac="52:54:$(dd if=/dev/urandom count=1 2>/dev/null | md5sum | sed -r 's/^(..)(..)(..)(..).*$/\1:\2:\3:\4/')"
base_xml=${xml_dir}/centos6u8_base.xml
virsh destroy ${vm_name} &>/dev/null
virsh undefine ${vm_name} &>/dev/null
rm -rf ${xml_dir}/${vm_xml}
rm -rf ${images_dir}/${vm_name}.*
#disk
qemu-img create -f qcow2 -b ${images_dir}/${centos6u8_base_img} ${images_dir}/${vm_disk} &>/dev/null
#xml
wget -q ftp://10.18.40.100/kvm/base_xml/${centos6u8_base_xml} -O ${base_xml}
cp ${base_xml} ${vm_xml}
sed -i -r "s#VM_NAME#$vm_name#" ${vm_xml}
sed -i -r "s#VM_UUID#$vm_uuid#" ${vm_xml}
sed -i -r "s#VM_DISK#$vm_disk#" ${vm_xml}
sed -i -r "s#VM_MAC#$vm_mac#" ${vm_xml}
#define
virsh define ${vm_xml} &>/dev/null
echo "虚拟机${vm_name} 重置完成..."
done
;;
3)
conn_test
download_kvm_script
read -p "确认重置所有的CentOS7.3虚拟机吗?[y]: " rebuild_centos7u3
if [ ! "${rebuild_centos7u3}" = "y" ];then
echo -e "$red_col输入不正确! $reset_col"
continue
fi
if [ ! -f ${images_dir}/${centos7u3_base_img} ];then
echo "正在下载镜像文件，请稍候......"
wget -O ${images_dir}/${centos7u3_base_img} ftp://10.18.40.100/kvm/base_image/${centos7u3_base_img}
fi
for i in {1..5}
do
vm_name=centos7u3-${i}
vm_uuid=$(uuidgen)
vm_disk=${vm_name}.qcow2
vm_xml=${xml_dir}/${vm_name}.xml
vm_mac="52:54:$(dd if=/dev/urandom count=1 2>/dev/null | md5sum | sed -r 's/^(..)(..)(..)(..).*$/\1:\2:\3:\4/')"
base_xml=${xml_dir}/centos7u3_base.xml
virsh destroy ${vm_name} &>/dev/null
virsh undefine ${vm_name} &>/dev/null
rm -rf ${xml_dir}/${vm_xml}
rm -rf ${images_dir}/${vm_name}.*
#disk
qemu-img create -f qcow2 -b ${images_dir}/${centos7u3_base_img} ${images_dir}/${vm_disk} &>/dev/null
#xml
wget -q ftp://10.18.40.100/kvm/base_xml/${centos7u3_base_xml} -O ${base_xml}
cp ${base_xml} ${vm_xml}
sed -i -r "s#VM_NAME#$vm_name#" ${vm_xml}
sed -i -r "s#VM_UUID#$vm_uuid#" ${vm_xml}
sed -i -r "s#VM_DISK#$vm_disk#" ${vm_xml}
sed -i -r "s#VM_MAC#$vm_mac#" ${vm_xml}
#define
virsh define ${vm_xml} &>/dev/null
echo "虚拟机${vm_name} 重置完成..."
done
;;
4)
conn_test
download_kvm_script
read -p "确认重置 windows 7 虚拟机吗?[y]: " rebuild_win7
if [ ! "${rebuild_win7}" = "y" ];then
echo -e "$red_col输入不正确! $reset_col"
continue
fi
if [ ! -f ${images_dir}/${win7_base_img} ];then
echo "正在下载镜像文件，请稍候......"
wget -O ${images_dir}/${win7_base_img} ftp://10.18.40.100/kvm/base_image/${win7_base_img}
fi
virsh destroy win7 &>/dev/null
virsh undefine win7 &>/dev/null
rm -rf ${xml_dir}/win7.xml
rm -rf ${images_dir}/win7.qcow2
qemu-img create -f qcow2 -b ${images_dir}/${win7_base_img} ${images_dir}/win7.qcow2 &>/dev/null
wget -q ftp://10.18.40.100/kvm/base_xml/win7_base.xml -O ${xml_dir}/win7.xml
virsh define ${xml_dir}/win7.xml &>/dev/null
echo "虚拟机 windows 重置完成..."
;;
5)
conn_test
download_kvm_script
all_vm=$(virsh list --all |awk '/[0-9]/{print $2}')
echo -en "${red_col}确认删除所有虚拟机吗?[y]:${reset_col} "
read delete_all
if [ ! "${delete_all}" = "y" ];then
echo -e "$red_col放弃删除! $reset_col"
continue
fi
for vm in ${all_vm}
do
virsh destroy $vm &>/dev/null
virsh undefine $vm &>/dev/null
rm -rf ${xml_dir}/${vm}.xml
rm -rf ${images_dir}/${vm}*
echo "已删除虚拟机 $vm"
done
;;
m)
clear
menu
;;
q)
exit
;;
'')
;;
*)
echo "输入错误！"
esac
done
```