Virtual machine installation is not low operation, snapshot creation, virtual machine management

                                                 Install the virtual machine

1. Modify the virtual machine settings with a script:

   1  cd /mnt

   2 vim vm_create.sh #Edit and install virtual machine and virtual machine setup script

******vm_create.sh******

#!/bin/bash #Magic number (magic number check is used to check whether the file has special fixed format data, when you see the first line of characters, you will understand the file attributes)

virt-install \ #Install the virtual machine

--cdrom /home/kiosk/Desktop/rhel-server-7.0-x86_64-dvd.iso \ #installation location

--ram 1024 \ #memory size

--cpus 1 \ #cpu number

--disk /var/lib/libvirt/images/$1.qcow2,#hard disk location size=9#hard disk size,bus=virtio \ #hard disk type

--name $1 \ #Specify the virtual machine name

--network source=br0,model=virtio #network type

   3 chmod +x /mnt/vm_create.sh #Add executable permission

   4 sh vm_create.sh westos #Run the script

   2. Manually install the virtual machine

********Take a snapshot of a virtual machine********

##1. Make a snapshot with the command

[root@foundation32 ~]# cd /var/lib/libvirt/

[root@foundation32 libvirt]# cd images/

2.ls #View virtual machine master disk

3.qemu-img create -f qcow2 -b westos.qcow2 new.qcow2

                                #Make a snapshot; backup westos.qcow2 to new.qcow2

 

##2. Make snapshots with scripts

[root@foundation64 mnt]# cd /var/lib/libvirt/images/

[root@foundation64 images]# ls

fafa.qcow2               rh124-desktop.xml

new.qcow2                rh124-server-vda.ovl

rh124-desktop-vda.ovl    rh124-server-vda.qcow2

rh124-desktop-vda.qcow2  rh124-server-vdb.ovl

rh124-desktop-vdb.ovl    rh124-server-vdb.qcow2

rh124-desktop-vdb.qcow2  rh124-server.xml

[root@foundation64 images]# rm -f new.qcow2

[root@foundation64 images]# cd /etc/libvirt/qemu/

[root@foundation64 qemu]# ls

desktop.xml  fafa.xml  networks  new.xml  server.xml

[root@foundation64 qemu]# rm -f new.xml

[root@foundation64 qemu]# cd /mnt/

[root@foundation64 mnt]# ls

vm_create.sh  

[root@foundation64 mnt]# vim vm_sanpshoot.sh

#！/bin/bash

qemu-img create -f qcow2 -b \ #Make a snapshot

/var/lib/libvirt/images/$1.qcow2 \

/var/lib/libvirt/images/$2.qcow2

virt-install \

The second character after the --name $2 \ # character is the snapshot name

--cpus 1 \ #Number of snapshot CPUs

--ram 1024 \ #RAM

--disk /var/lib/libvirt/images/$2.qcow2,#hard disk location bus=virtio \#hard disk type

--import & #Execute in background

[root@foundation64 mnt]# chmod +x vm_sanpshoot.sh #Add executable permission

[root@foundation64 mnt]# /mnt/vm_sanpshoot.sh    fafa   new2

 # means to run the snapshot program, the master disk is fafa, and the snapshot is new2

Formatting '/var/lib/libvirt/images/new2.qcow2', fmt=qcow2 size=9663676416 backing_file='/var/lib/libvirt/images/fafa.qcow2' encryption=off cluster_size=65536 lazy_refcounts=off

[root@foundation64 mnt]# WARNING  No operating system detected, VM performance may suffer. Specify an OS with --os-variant for optimal results.

Starting install...
Creating domain...                       |    0 B     00:00     

(virt-viewer:10466): GSpice-WARNING **: Warning no automount-inhibiting implementation available

3. Virtual machine management:

 1 cd /var/lib/libvirt/images/ #hard disk location

 2   mv westos.qcow2 /mnt/

 3 cd /etc/libvirt/qemu/ #Location of hard disk information

 4 ls

 5 mv westos.xml / mnt /

 6   cd /mnt/

 7 ls

 8   mv westos.qcow2 /var/lib/libvirt/images/

 9 ls

#The reason why we need to remove the hardware information and hard disk of the westos virtual machine is to delete the icon and then move it back to the original location to restore it directly, so as to avoid wasting time for re-downloading, and friends can also do experiments#

10 virsh create westos.xml #One-time recovery

[root@foundation64 mnt]# virsh create new.xml

Domain new created from new.xml

   ***It will disappear automatically after shutdown new virtual machine**

 11 virsh define new.xml #Permanent recovery

[root@foundation64 mnt]# virsh define new.xml

Domain new defined from new.xml

  12 virsh undefined new #delete icon

[root@foundation64 mnt]# virsh undefine new

Domain new has been undefined

#It can be restored after deletion, because only the icon is deleted, and the hardware information and hard disk are not deleted

[root@foundation64 mnt]# virsh define new.xml

Domain new defined from new.xml

 13 virsh start new #Run the specified vm

[root@foundation64 mnt]# virsh start new

Domain new started

14 virsh destroy new #Forcibly end

[root@foundation64 mnt]# virsh destroy new

Domain new destroyed

  15 virsh showdown new #Normal shutdown

[root@foundation64 mnt]# virsh start new
Domain new started

[root@foundation64 mnt]# virsh shutdown new
Domain new is being shutdown

  16 virsh list --all #Display all virtual machine status

[root@foundation64 mnt]# virsh list --all

 Id Name State
--------------------------------------------------------- -----
 2 desktop running
 7 fafa running
 - new shut off
 - server shut off
  17 virt-viewer new #Visualization, similar to rht-vmctl view new