目录
一、原理
- 需要先创建基础镜像，后续的镜像都是基于该镜像创建的差量镜像。基础镜像不允许修改(需要注意)。
- 基础镜像需要设置要一些基本内容。
- 通过 virt-edit 实现的设置ip.
ip信息统一用<title>来进行标记。 使用virsh list --title进行查看 机器和IP
完成的功能：
输入机器名称和ip，就能创建我们想要的虚拟机了。ip会自动帮我们设置好。
解决的问题：
- 之前创建机器后需要手动去设置IP.
virt-edit进行编辑网络文件。 - 创建完机器，我们不知道机器对应的哪个IP. 使用
<title>来进行标记。 使用virsh list --title进行查看 机器和IP对应关系
二、基础镜像
2.1、创建基础镜像
- 内存为8G 和2核
- 磁盘为50G
- vnc 端口使用随机
- 网络设置为桥接
- 机器设置为自动启动
virt-install --name base-image --virt-type kvm --memory 8096 --vcpus 2 --cdrom=/home/kvm/iso/CentOS-7-x86_64-Minimal-1908.iso --disk /home/kvm/data/base-image.qcow2,size=50,format=qcow2 --graphics vnc,listen=0.0.0.0 --network network=net-br --autostart
2.2、 完善基础镜像
-
增加 console 登陆
grubby --update-kernel=ALL --args="console=ttyS0,115200n8" -
vnc 端口设置随机
-
使用桥接网络
-
设置网络配置
BOOTPROTO=static ONBOOT=yes IPADDR=192.168.1.12 NETMASK=255.255.255.0 GATEWAY=192.168.1.1 DNS1=192.168.1.1 # 注释uuid
2.3、基础镜像设置权限
由于使用的是差量镜像的模式，所以基础镜像不允许修改。
chattr +i /opt/kvm/data/base-image.qcow2
3.4 设置 title
编辑基础镜像的 xml 文件，增加 title。
<title>192.168.1.156</title>
3.5、基础镜像XML
<!--
WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
OVERWRITTEN AND LOST. Changes to this xml configuration should be made using:
virsh edit base-image
or other application using the libvirt API.
-->
<domain type='kvm'>
<name>base-image</name>
<uuid>12348899-e829-4217-a0ff-f30eee4d2b31</uuid>
<title>192.168.1.199</title>
<memory unit='KiB'>16777216</memory>
<currentMemory unit='KiB'>8388608</currentMemory>
<vcpu placement='static' current='2'>4</vcpu>
<os>
<type arch='x86_64' machine='pc-i440fx-rhel7.0.0'>hvm</type>
<boot dev='hd'/>
</os>
<features>
<acpi/>
<apic/>
</features>
<cpu mode='custom' match='exact' check='partial'>
<model fallback='allow'>Broadwell-IBRS</model>
<feature policy='require' name='spec-ctrl'/>
</cpu>
<clock offset='utc'>
<timer name='rtc' tickpolicy='catchup'/>
<timer name='pit' tickpolicy='delay'/>
<timer name='hpet' present='no'/>
</clock>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<pm>
<suspend-to-mem enabled='no'/>
<suspend-to-disk enabled='no'/>
</pm>
<devices>
<emulator>/usr/libexec/qemu-kvm</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/opt/kvm/data/base-image.qcow2'/>
<target dev='vda' bus='virtio'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
</disk>
<disk type='file' device='cdrom'>
<driver name='qemu' type='raw'/>
<target dev='hda' bus='ide'/>
<readonly/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
<controller type='usb' index='0' model='ich9-ehci1'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x7'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci1'>
<master startport='0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0' multifunction='on'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci2'>
<master startport='2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x1'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci3'>
<master startport='4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x2'/>
</controller>
<controller type='pci' index='0' model='pci-root'/>
<controller type='ide' index='0'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
</controller>
<controller type='virtio-serial' index='0'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
</controller>
<interface type='network'>
<mac address='52:54:00:28:99:22'/>
<source network='net-br'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
<serial type='pty'>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
</serial>
<console type='pty'>
<target type='serial' port='0'/>
</console>
<channel type='unix'>
<target type='virtio' name='org.qemu.guest_agent.0'/>
<address type='virtio-serial' controller='0' bus='0' port='1'/>
</channel>
<input type='tablet' bus='usb'>
<address type='usb' bus='0' port='1'/>
</input>
<input type='mouse' bus='ps2'/>
<input type='keyboard' bus='ps2'/>
<graphics type='vnc' port='-1' autoport='yes' listen='0.0.0.0' keymap='en-us'>
<listen type='address' address='0.0.0.0'/>
</graphics>
<video>
<model type='cirrus' vram='16384' heads='1' primary='yes'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
</video>
<memballoon model='virtio'>
<address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
</memballoon>
<rng model='virtio'>
<backend model='random'>/dev/urandom</backend>
<address type='pci' domain='0x0000' bus='0x00' slot='0x08' function='0x0'/>
</rng>
</devices>
</domain>
三、批量创建机器脚本
因为需要使用 virt-edit，所以需要安装
libguestfs-tools
yum install -y libguestfs-tools
#!/bin/bash
#######################################################
# $Name: create_kvm_machine.sh
# $Version: v1.0
# $Function: create kvm machine
# $Author: dongjiaxiao
# $Create Date: 2020-04-12
# $Description: shell
######################################################
#set -x
# 检查基础镜像和xml是否存在并生成uuid，mac 信息
function check(){
if [ ! -f "${xmls_dir}${base_xml}" ]&&[ ! -f "${images_dir}${base_img}" ] # 判断基础xml和基础镜像是否存在
then
echo "基础镜像或者基础镜像xml不存在"
exit 1
else
vir_uuid=`uuidgen`
vir_mac="52:54:$(dd if=/dev/urandom count=1 2>/dev/null | md5sum |sed -r 's/^(..)(..)(..)(..).*$/1:2:3:4/')"
vir_name=$machine_name
fi
}
#创建磁盘
function create_disk(){
chattr -i ${images_dir}$base_img
qemu-img create -f qcow2 -b ${images_dir}$base_img ${images_dir}${vir_name}.qcow2 ${vir_disk}G &>/dev/null
}
#添加磁盘
function attach_disk(){
qemu-img create -f qcow2 ${images_dir}${vir_name}-2.qcow2 ${vir_attach_disk}G >/dev/null
virsh attach-disk ${vir_name} ${images_dir}${vir_name}-2.qcow2 vdb --cache writeback --subdriver qcow2 --persistent >/dev/null
}
#配置xml ，替换内存cpu 等信息并导入
function conf_xml(){
cp ${xmls_dir}${base_xml} /tmp/${vir_name}.xml
sed -i "s#<memory unit='KiB'>.*</memory>#<memory unit='KiB'>${vir_mem}</memory>#" /tmp/${vir_name}.xml
sed -i "s#<currentMemory unit='KiB'>.*</currentMemory>#<currentMemory unit='KiB'>${vir_mem}</currentMemory>#" /tmp/${vir_name}.xml
sed -i "s#<vcpu placement='static'>.*</vcpu>#<vcpu placement='static'>${vir_cpu}</vcpu>#" /tmp/${vir_name}.xml
sed -i "s/<name>.*</name>/<name>${vir_name}</name>/" /tmp/${vir_name}.xml
sed -i "s/<uuid>.*</uuid>/<uuid>${vir_uuid}</uuid>/" /tmp/${vir_name}.xml
sed -i "s/<title>.*</title>/<title>${vir_ip}</title>/" /tmp/${vir_name}.xml
sed -i "s#<source file=.*/>#<source file='${images_dir}${vir_name}.qcow2'/>#" /tmp/${vir_name}.xml
sed -i "s/<mac address=.*/>/<mac address='$vir_mac' />/" /tmp/${vir_name}.xml
virsh define /tmp/${vir_name}.xml >/dev/null
virt-edit -d ${vir_name} /etc/sysconfig/network-scripts/ifcfg-eth0 -e "s#IPADDR=".*"#IPADDR="${vir_ip}"#" # 替换ip
}
#启动并设置开机自启
function start_vir(){
virsh start ${vir_name} >/dev/null
virsh autostart ${vir_name} >/dev/null
chattr +i ${images_dir}$base_img
}
#记录创建日志
function create_vir_log(){
echo "$(date +%F_%T) vir_name: ${vir_name} vir_ip: ${vir_ip} !" >>$vir_log_file
echo "$(date +%F_%T) vir_name: ${vir_name} vir_ip: ${vir_ip} 创建成功!"
}
main(){
images_dir="/home/kvm/data/" # 镜像存储的位置
base_img="base-image.qcow2" # 基础镜像的名称
xmls_dir="/etc/libvirt/qemu/" # xml 的位置
base_xml="base-image.xml" # 基础xml的名称
vir_log_file="/tmp/kvm_create_log.txt" # 创建日志文件
vir_disk=50 # 磁盘默认为50G
vir_cpu=2 # cpu默认为2核
vir_mem=8388608 # 内存默认为8G
echo -e "服务器配置选项:
1: 2核8G 50G(测试)
2: 1核8G 50G(开发)
3: 2核8G 100G(数据库)
4: 4核20G 200G"
read -t 30 -p "输入你选择的配置的编号(1-4):" number
read -t 90 -p "输入想要创建的IP(192.168.1.1):" vir_ip
read -t 120 -p "输入想要创建的机器名称(haha-biz-1234567-test):" machine_name
if [ -z "$vir_ip" ] || [ -z "$machine_name" ] # 判断是否输入ip和机器名称
then
echo "请输入ip和机器名称"
exit -1
fi
case "$number" in
[1] )
check
create_disk
conf_xml
start_vir
create_vir_log
;;
[2] )
vir_cpu=1 # 设置为1核
check
create_disk
conf_xml
start_vir
create_vir_log
;;
[3] )
vir_disk=100 #设置为磁盘100G盘
check
create_disk
conf_xml
start_vir
create_vir_log
;;
[4] )
base_img="dc-base-image.qcow2"
vir_cpu=4 # 设置为4核
vir_mem=20971520 #设置内存为20G
vir_disk=20 #设置为磁盘200G盘
vir_attach_disk=200 # 设置附加盘的大小
check
create_disk
conf_xml
start_vir
attach_disk
create_vir_log
;;
*) echo "输入编号(1-4)";;
esac
}
main
四、挂载磁盘多种方式
扩展对象为： 虚拟机
4.1 扩容现有的磁盘
- 这种方式只能增加不能缩小
- 需要先把虚拟机关闭。(注意)
-
宿主机操作
[root@djx-kvm-123456-test opt]# virsh shutdown djx-mysql-djxmysq-test [root@djx-kvm-123456-test opt]# qemu-img info /home/kvm/data/djx-mysql-djxmysq-test.qcow2 image: /home/kvm/data/djx-mysql-djxmysq-test.qcow2 file format: qcow2 virtual size: 100G (107374182400 bytes) disk size: 131M cluster_size: 65536 backing file: /home/kvm/data/base-image.qcow2 Format specific information: compat: 1.1 lazy refcounts: false [root@djx-kvm-af3r34t-test opt]# qemu-img resize /home/kvm/data/djx-mysql-djxmysq-test.qcow2 +3G Image resized. [root@djx-kvm-af3r34t-test opt]# qemu-img info /home/kvm/data/djx-mysql-djxmysq-test.qcow2 image: /home/kvm/data/djx-mysql-djxmysq-test.qcow2 file format: qcow2 virtual size: 103G (110595407872 bytes) disk size: 254M cluster_size: 65536 backing file: /home/kvm/data/base-image.qcow2 Format specific information: compat: 1.1 lazy refcounts: false -
虚拟机操作
虚拟机可以进行两种类型的操作：(以下两步是冲突的，只能2选1)
1、是使用新增空间扩容现有的磁盘
2、是使用新增空间创建新的分区
-
使用新增空间扩容现有的磁盘
# 内核版本大于3.6.0 # 安装 growpart或者xfsprogs扩容格式化工具 yum install cloud-utils-growpart yum install xfsprogs # 运行fdisk -l命令查看现有云盘大小 [root@localhost ~]# df -h Filesystem Size Used Avail Use% Mounted on devtmpfs 3.9G 0 3.9G 0% /dev tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs 3.9G 8.5M 3.9G 1% /run tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup /dev/vda2 50G 1.2G 49G 3% / /dev/vda1 497M 134M 363M 27% /boot tmpfs 783M 0 783M 0% /run/user/0 [root@localhost ~]# fdisk -l Disk /dev/vda: 107.4 GB, 107374182400 bytes, 209715200 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x000a6596 Device Boot Start End Blocks Id System /dev/vda1 * 2048 1026047 512000 83 Linux /dev/vda2 1026048 104857599 51915776 83 Linux # 查看分区的文件系统类型 [root@localhost ~]# blkid /dev/vda2 /dev/vda2: UUID="be6f97e3-13c3-46ea-9694-78a575272bb8" TYPE="xfs" # 调用growpart为需要扩容的云盘和对应的第几个分区扩容 [root@localhost ~]# growpart /dev/vda 2 CHANGED: partition=2 start=1026048 old: size=103831552 end=104857600 new: size=208689119 end=209715167 # 运行xfs_growfs <PartitionName>命令调用xfs_growfs扩容文件系统。 # xfs 文件系统使用xfs_growfs ，ext4 文件系统使用 resize2fs [root@localhost ~]# xfs_growfs /dev/vda2 meta-data=/dev/vda2 isize=512 agcount=4, agsize=3244736 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0 spinodes=0 data = bsize=4096 blocks=12978944, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal bsize=4096 blocks=6337, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 data blocks changed from 12978944 to 26086139 -
使用新增空间创建新的分区(与上一步冲突的)
[root@localhost ~]# fdisk /dev/vda Welcome to fdisk (util-linux 2.23.2). Changes will remain in memory only, until you decide to write them. Be careful before using the write command. Command (m for help): m Command action a toggle a bootable flag b edit bsd disklabel c toggle the dos compatibility flag d delete a partition g create a new empty GPT partition table G create an IRIX (SGI) partition table l list known partition types m print this menu n add a new partition o create a new empty DOS partition table p print the partition table q quit without saving changes s create a new empty Sun disklabel t change a partition's system id u change display/entry units v verify the partition table w write table to disk and exit x extra functionality (experts only) Command (m for help): n Partition type: p primary (2 primary, 0 extended, 2 free) e extended Select (default p): p Partition number (3,4, default 3): First sector (104857600-209715199, default 104857600): Using default value 104857600 Last sector, +sectors or +size{K,M,G} (104857600-209715199, default 209715199): Using default value 209715199 Partition 3 of type Linux and of size 50 GiB is set Command (m for help): w The partition table has been altered! Calling ioctl() to re-read partition table. WARNING: Re-reading the partition table failed with error 16: Device or resource busy. The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8) Syncing disks. [root@localhost ~]# fdisk -l Disk /dev/vda: 107.4 GB, 107374182400 bytes, 209715200 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x000a6596 Device Boot Start End Blocks Id System /dev/vda1 * 2048 1026047 512000 83 Linux /dev/vda2 1026048 104857599 51915776 83 Linux /dev/vda3 104857600 209715199 52428800 83 Linux # 然后需要重启机器。不然直接挂载的话是挂载不了的。 # 格式化磁盘 [root@localhost ~]mkfs.xfs /dev/vda3 [root@localhost ~]# mount /dev/vda3 /home # 如果没有重启 ，报错 mount: special device /dev/vda3 does not exist # 还需要设置开动挂载
4.2 添加新的磁盘
-
宿主机操作
[root@k5-m2 ~]# qemu-img create -f qcow2 /home/kvm/data/djx-biz-djx1234-dev-2.qcow2 10G Formatting '/home/kvm/data/djx-biz-djx1234-dev-2.qcow2', fmt=qcow2 size=10737418240 encryption=off cluster_size=65536 lazy_refcounts=off [root@k5-m2 ~]# virsh attach-disk djx-biz-djx1234-dev /home/kvm/data/djx-biz-djx1234-dev-2.qcow2 vdb --cache writeback --subdriver qcow2 --persistent Disk attached successfully [root@djx-kvm-af3r34t-test data]# virsh domblklist djx-biz-djx1234-dev Target Source ------------------------------------------------ vda /home/kvm/data/djx-biz-djx1234-dev.qcow2 vdb /home/kvm/data/djx-biz-djx1234-dev-2.qcow2 hda - -
虚拟机操作
[root@localhost ~]# fdisk -l Disk /dev/vda: 85.9 GB, 85899345920 bytes, 167772160 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x000a6596 Device Boot Start End Blocks Id System /dev/vda1 * 2048 1026047 512000 83 Linux /dev/vda2 1026048 104857599 51915776 83 Linux /dev/vda3 104857600 167772126 31457263+ 83 Linux Disk /dev/vdb: 10.7 GB, 10737418240 bytes, 20971520 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes # 我们可以在系统盘这边看到我们新增加的磁盘，然后我们可以对该磁盘进行初始化和分区，并挂载使用了，注意在挂载的时候需要注意设置开机自动挂载。 具体操作见 7.1 虚拟机操作-使用新增空间创建新的分区
五、常用操作命令
-
查看虚拟机对应的ip
virsh list --title -
登录虚拟机
-
通过 console
virsh console djx-biz-qawsed4-test -
通过 ssh
-
通过 vnc
vnc 端口为随机。通过查找对应的进程来获取。
-
-
virsh list [--all] #查看所有KVM虚拟机 -
virsh dominfo name# 查看虚拟机 CPU/内存的使用率 -
virsh start name #启动KVM虚拟机 -
virsh shutdown name #正常关闭KVM虚拟机、基本是关不掉的 -
virsh autostart name# 设置开机自启 -
virsh autostart –disable name# 关闭开机自启 -
virsh destroy name #强制关闭KVM虚拟机(类似于直接断电) -
virsh suspend name #挂起KVM虚拟机 -
virsh resume name #恢复挂起的KVM虚拟机 -
virsh dumpxml name #查看KVM虚拟机配置文件 -
virsh edit name #编辑KVM虚拟机的xml配置文件 -
virsh undefine name #彻底删除KVM虚拟机,不可逆,如果想找回来,需要备份/etc/libvirt/qemu的xml文件 -
virsh snapshot-create name #创建快照 -
virsh snapshot-delete name --current/--snapshotname #删除快照 -
virsh snapshot-dumpxml name #导出XML -
virsh snapshot-list name #查看快照