虚拟机快照：虚拟化技术概述 虚拟机安装与管理手册

[root@foundation3 ~]# virt-install --name mo1 --ram 1024 --file /var/lib/li 
bvirt/images/mo1.img --cdrom /root/Desktop/rhel-server-7.1-x86_64-dvd.iso - 
-file-size 8 
WARNING No operating system detected, VM performance may suffer. Specify an OS 
with --os-variant for optimal results. 
WARNING CDROM media does not print to the text console by default, so you likel 
y will not see text install output. You might want to use --location.See the man 
 page for examples of using --location with CDROM media 
 
Starting install... 
Allocating 'mo1.img'         | 8.0 GB  00:00 
Creating domain...         | 0 B  00:00 
Connected to domain mo1 

[root@foundation3 ~]# ls /etc/libvirt/qemu /var/lib/libvirt/images/ 
/etc/libvirt/qemu: 
desktop.xml <span style="color:#ff0000;">mo.xml</span> networks server.xml 
 
/var/lib/libvirt/images/: 
mo1.img    rh124-desktop-vda.qcow2 rh124-server-vda.ovl rh124-server.xml 
<span style="color:#ff0000;">mo.img</span>     rh124-desktop-vdb.ovl rh124-server-vda.qcow2 test.sh 
mo_shot.qcow2   rh124-desktop-vdb.qcow2 rh124-server-vdb.ovl vm1.qcow2 
rh124-desktop-vda.ovl rh124-desktop.xml  rh124-server-vdb.qcow2 

[root@foundation3 ~]# virsh list 
 Id Name       State 
---------------------------------------------------- 

[root@foundation3 ~]# virsh start mo 
Domain mo started 
 
[root@foundation3 ~]# virsh list 
 Id Name       State 
---------------------------------------------------- 
 9  mo        running 
 
[root@foundation3 ~]# su - mo 
Last login: Wed Oct 19 10:48:59 CST 2016 on pts/3 
[mo@foundation3 ~]$ virsh list 
 Id Name       State 
---------------------------------------------------- 

[root@foundation3 ~]# virt-install --name zhao --ram 1024 --file /var/lib/libvirt/images/zhao.img --file-size 8 --cdrom /root/Desktop/rhel-server-7.1-x86_64-dvd.iso 
WARNING No operating system detected, VM performance may suffer. Specify an OS with --os-variant for optimal results. 
WARNING CDROM media does not print to the text console by default, so you likely will not see text install output. You might want to use --location.See the man page for examples of using --location with CDROM media 
 
Starting install... 
Allocating 'zhao.img'            | 8.0 GB 00:00:00  
<span style="color:#ff0000;">ERROR </span> internal error: process exited while connecting to monitor: 2016-10-19T03:00:25.552714Z qemu-kvm: -drive file=/root/Desktop/rhel-server-7.1-x86_64-dvd.iso,if=none,id=drive-ide0-0-1,readonly=on,format=raw: <span style="color:#ff0000;">could not open disk image /root/Desktop/rhel-server-7.1-x86_64-dvd.iso: Could not open file: Permission denied</span> 
 
Domain installation does not appear to have been successful. 
If it was, you can restart your domain by running: 
 virsh --connect qemu:///system start zhao 
otherwise, please restart your installation. 

[root@foundation3 ~]# ll /root/Desktop/rhel-server-7.1-x86_64-dvd.iso 
-rw-r--r-- 1 qemu qemu 3890216960 Oct 17 22:15 /root/Desktop/rhel-server-7.1-x86_64-dvd.iso 

<span style="color:#ff0000;">#user = "root"</span> 
 
# The group for QEMU processes run by the system instance. It can be 
# specified in a similar way to user. 
<span style="color:#ff0000;">#group = "root"</span> 
 
# Whether libvirt should dynamically change file ownership 
# to match the configured user/group above. Defaults to 1. 
# Set to 0 to disable file ownership changes. 
<span style="color:#ff0000;">#dynamic_ownership =0 </span> 

[root@foundation3 ~]# virsh list --all 
 Id Name       State 
---------------------------------------------------- 
 -  desktop      shut off 
 -  mo        shut off 
 -  server       shut off

[root@foundation3 ~]# qemu-img create -f qcow2 -b /var/lib//libvirt/images/mo.img /var/lib/libvirt/images/test.qcow2 
Formatting '/var/lib/libvirt/images/test.qcow2', fmt=qcow2 size=8589934592 backing_file='/var/lib//libvirt/images/mo.img' encryption=off cluster_size=65536 lazy_refcounts=off 
[root@foundation3 ~]# ls /var/lib/libvirt/images/ 
mo1.img     rh124-desktop-vdb.ovl rh124-server-vdb.ovl vm1.qcow2 
mo.img     rh124-desktop-vdb.qcow2 rh124-server-vdb.qcow2 zhao.img 
mo_shot.qcow2   rh124-desktop.xml  rh124-server.xml 
rh124-desktop-vda.ovl rh124-server-vda.ovl  <span style="color:#ff0000;">test.qcow2</span> 
rh124-desktop-vda.qcow2 rh124-server-vda.qcow2 test.sh 
[root@foundation3 ~]# 

#!/bin/bash 
create_img() 
{ 
  
 virsh undefine $1 &>/dev/null 
 qemu-img create -f qcow2 -b /var/lib/libvirt/images/$1.img /var/lib/libvirt/images/$1_shot.qcow2 &>/dev/null 
 virt-install --name $1 --ram 1024 --disk /var/lib/libvirt/images/$1_shot.qcow2 --import --noautoconsole &>/dev/null 
 virsh define /etc/libvirt/qemu/$1.xml &>/dev/null 
} 
delete_img() 
{ 
 virsh undefine $1 &>/dev/null 
 rm -rf /var/lib/libvirt/images/$1_shot.qcow2 &>/dev/null 
} 
check_status() 
{ 
 status=`virsh list --all| sed -n '3,$p'|sed 's/[[:space:]]\+/:/g'|grep $1 |cut -d':' -f4` 
 echo $status 
 if [ $status = "shut" ];then 
  return 0 
 elif [ $status = 'running' ];then 
  return 1 
 fi 
} 
case $1 in 
--start|-s) 
shift 
 
echo "start $1 ..." 
check_status $1 &>/dev/null && virsh start $1 &>/dev/null 
;; 
--view|-v) 
shift 
echo "view $1 ..." 
check_status $1 &> /dev/null || virt-viewer $1 &>/dev/null & 
;; 
--shutdown|-d) 
shift 
echo "shutdown $1 ..." 
check_status $1 &> /dev/null || virsh destroy $1 &>/dev/null & 
;; 
--create|-c) 
shift 
check_status $1 &> /dev/null || virsh destroy $1 
echo "create snapshot for $1 ..." 
create_img $1 
echo "success create snapshot" 
;; 
--reset|-r) 
shift 
check_status &>/dev/null $1 || virsh destroy $1 
delete_img $1 
create_img $1 
;; 
--check|-h) 
shift 
echo $1 `check_status $1` 
;; 
*) 
echo "vmctl <COMMAND> <OPTIONS> " 
echo "" 
echo "open,show,shutdown,reset...Virtual Machine" 
echo -e "--start|-s\topen Virtual Machine\n--view|-v\tshow the Virtual Machine that has been opened" 
echo -e "--shutdown|-d\tclose your Virtual Machine" 
echo -e "--create|-c\tcreate a snapshot for your Virtual Machine" 
echo -e "--reset|-r\treset your Virtual Machine" 
echo -e "--check|-h\tcheck Virtual Machine status running or shut" 
;; 
esac