Centos 7 最小化kvm部署

1、检查CPU是否支持虚拟化

sh-4.2# grep -E '(vmx|svm)' /proc/cpuinfo
# 若是无任何显示，则表示CPU不支持kvm虚拟化

2、关闭selinux

sh-4.2# sed -i '1,$ s/enforcing/disabled/g' /etc/selinux/config
sh-4.2# reboot

3、卸载防火墙

sh-4.2# rpm -qa | grep "iptables" | xargs rpm -e --nodeps
sh-4.2# rpm -qa | grep "firewall" | xargs rpm -e --nodeps

4、配置本地源

sh-4.2# cat /etc/yum.repos.d/GuGe.repo 
[GuGe]
name=GuGe
baseurl=ftp://192.168.1.125
gpgcheck=0
enable=1
# 这里仅使用了iso镜像源

5、安装软件

sh-4.2# yum install qemu-kvm libvirt virt-install bridge-utils -y

# 检查安装是否成功，如果出现下列显示，则表示成功
sh-4.2# lsmod | grep kvm
kvm_intel             170086  0 
kvm                   566340  1 kvm_intel
irqbypass              13503  1 kvm

6、启动程序

sh-4.2# systemctl start libvirtd
sh-4.2# systemctl enable libvirtd

7、配置程序

# 配置桥接网卡
sh-4.2# vi /etc/sysconfig/network-scripts/ifcfg-br0
sh-4.2# cat /etc/sysconfig/network-scripts/ifcfg-br0 
BOOTPROTO=static
DEVICE=br0
TYPE=Bridge
NM_CONTROLLED=no
IPADDR=192.168.1.125
NETMASK=255.255.255.0
GATEWAY=192.168.1.1
DNS1=8.8.8.8

sh-4.2# cp /etc/sysconfig/network-scripts/ifcfg-enp7s0 /etc/sysconfig/network-scripts/ifcfg-enp7s0.bak
sh-4.2# vi /etc/sysconfig/network-scripts/ifcfg-enp7s0
sh-4.2# cat /etc/sysconfig/network-scripts/ifcfg-enp7s0
BOOTPROTO=none
DEVICE=enp7s0
NM_CONTROLLED=no
ONBOOT=yes
BRIDGE=br0
sh-4.2# systemctl restart network.service

sh-4.2# ifconfig br0
br0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.1.125  netmask 255.255.255.0  broadcast 192.168.1.255
        ether 00:e0:2b:68:0a:ad  txqueuelen 1000  (Ethernet)
        RX packets 78  bytes 5593 (5.4 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 57  bytes 6390 (6.2 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        
# 配置kvm虚拟机存放位置，这里就做过多描述了；看后续操作即可明白

sh-4.2# parted /dev/sdb 
GNU Parted 3.1
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) mkpart                                                           
Error: /dev/sdb: unrecognised disk label
(parted) mk                                                               
mklabel  mkpart   mktable  
(parted) mklabel 
New disk label type? gpt                                                  
(parted) mkpart /dev/sdb                                                 
File system type?  [ext2]? xfs                                            
Start? 1                                                                  
End? 2T
(parted) quit
Information: You may need to update /etc/fstab.

sh-4.2# partprobe 
sh-4.2# lsblk -f
NAME   FSTYPE LABEL UUID                                 MOUNTPOINT
sda                                                      
├─sda1 xfs          3abc71fb-6c9d-4fe6-a432-b5a48643f8bb /boot
├─sda2 xfs          fd28aad6-4cc8-48a7-beed-91624ea06746 /
├─sda3 swap         76b8f6e8-33b3-4fc0-90fc-b243c1d69cfb [SWAP]
└─sda4 xfs          b34c005c-15dd-4ade-b6d4-3cda14127116 /FTP
sdb                                                      
└─sdb1                                                   

sh-4.2# mkfs -t xfs /dev/sdb1 
meta-data=/dev/sdb1              isize=512    agcount=4, agsize=122094592 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=0, sparse=0
data     =                       bsize=4096   blocks=488378368, imaxpct=5
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=238466, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

sh-4.2# vi /etc/fstab
sh-4.2# grep -E -v '^$|^#' /etc/fstab 
UUID=fd28aad6-4cc8-48a7-beed-91624ea06746 /               xfs     defaults        0 0
UUID=3abc71fb-6c9d-4fe6-a432-b5a48643f8bb /boot           xfs     defaults        0 0
UUID=76b8f6e8-33b3-4fc0-90fc-b243c1d69cfb swap            swap    defaults        0 0
UUID=b34c005c-15dd-4ade-b6d4-3cda14127116 /FTP              xfs      defaults          0 0
UUID=eb08ac4c-9b16-491b-b735-9f5cecfd8ba6 /disk              xfs      defaults          0 0

sh-4.2# mkdir /disk
sh-4.2# mount -a
sh-4.2# lsblk -f
NAME   FSTYPE LABEL UUID                                 MOUNTPOINT
sda                                                      
├─sda1 xfs          3abc71fb-6c9d-4fe6-a432-b5a48643f8bb /boot
├─sda2 xfs          fd28aad6-4cc8-48a7-beed-91624ea06746 /
├─sda3 swap         76b8f6e8-33b3-4fc0-90fc-b243c1d69cfb [SWAP]
└─sda4 xfs          b34c005c-15dd-4ade-b6d4-3cda14127116 /FTP
sdb                                                      
└─sdb1 xfs          eb08ac4c-9b16-491b-b735-9f5cecfd8ba6 /disk

# 我这里已经准备好了ISO镜像，可以开始创建虚拟机了；我一般是用vnc操作虚拟机，也可以通过字符界面直接操作，我嫌太麻烦，就直接vnc操作了
# vnc下载地址：https://www.realvnc.com/en/connect/download/viewer/

sh-4.2# virt-install -n Centos7-1 -r 12288 --disk /disk/Centos7-1.img,format=qcow2,size=100 --vcpus=16 --network bridge=br0 --os-type=linux 
sh-4.2# --cdrom /FTP/ftp/镜像软件/iso/linux/Centos/7.4/CentOS-7-x86_64-Everything-1708.iso --vnc --vncport=5910 --vnclisten=0.0.0.0

8、开启宿主机远程连接虚拟机权限（可选操作）

sh-4.2# vim  /etc/default/grub
用如下内容覆盖原有内容：
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL="console serial"
GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
GRUB_CMDLINE_LINUX="rd.lvm.lv=centos/root rd.lvm.lv=centos/swap rhgb"
GRUB_CMDLINE_LINUX_DEFAULT="console=tty1 console=ttyS0,115200"
GRUB_DISABLE_RECOVERY="true"

sh-4.2# grub2-mkconfig -o /boot/grub2/grub.cfg
sh-4.2# reboot

sh-4.2# yum install -y acpid(客户端开启电源管理功能，这样就能在宿主机中设置虚拟机随宿主机启动而启动)

9、常用命令

virsh console vmname                在服务器端连接虚拟机
virsh shutdown vmname               关闭虚拟机
virsh list --all                    显示所有虚拟机及状态
virsh reboot vmname                 重启虚拟机
virsh start vmname                  启动虚拟机
virsh console vmname                连接虚拟机
ctrl + ]                            关闭连接
virsh suspend vmname                挂起虚拟机
virsh resume vmname                 恢复虚拟机
virsh dumpxml vmname                查看虚拟机配置详情
virsh autostart vmname              设置虚拟机随宿主机启动而启动
virsh autostart --disable vmname    取消虚拟机随宿主机启动而启动

virsh destroy vmname                强制关机
virsh undefine vmname               解除虚拟机，然后删除虚拟机文件(*.img)；这样才能彻底删除虚拟机，并且释放空间。

virsh start vmname --console        启动并远程连接
qemu-img create -f qcow2  /var/lib/libvirt/images/kvm01-1.img 20G    创建一个20G的磁盘文件，格式qcow2
virsh attach-disk vmname /var/lib/libvirt/images/kvm01-1.img vdb --cache=none --subdriver=qcow2     在线添加硬盘
virt-clone -o vmname1 -n vmname2 -f  /var/lib/libvirt/images/vmname02.img    克隆一个虚拟机


虚拟机信息的修改
virsh shutdown name
cd /etc/libvirt/qemu
virsh dumpxml old_name > new_name.xml
# 直接更改new_name.xml，更换想要更换的信息
virsh undefine old_name
virsh define new_name.xml
virsh list --all

10、参考地址

https://www.linuxidc.com/Linux/2017-01/140007.htm
http://blog.chinaunix.net/uid-30022178-id-5749329.html
https://blog.csdn.net/zxj1988/article/details/8530414
http://www.361way.com/virt-install/2721.html
https://blog.csdn.net/qq_37594711/article/details/61917902
https://www.cnblogs.com/createyuan/p/3741479.html
https://blog.csdn.net/wh211212/article/details/74908390
https://www.cnblogs.com/chenjiahe/p/5919426.html
https://www.linuxidc.com/Linux/2017-01/140009.htm?utm_source=tuicool&utm_medium=referral