Linux dump系统备份与还原
备份步骤：
1.创建系统：dd if=icp-centos54-64.img of=lvstest1.img bs=100M
2.创建备份块：dd if=/dev/zero of=backup.img bs=100M count=100
3.mkfs.ext3 backup.img
4.创建vm系统启动文件lvstest1.xml,内容如下：
<domain type='xen' id='-1'>
<name>lvstest1</name>
<uuid>a6603e99-fe4b-40bb-a076-aa56464f228f</uuid>
<memory>8388608</memory>
<currentMemory>524288</currentMemory>
<vcpu>1</vcpu>
<bootloader>/usr/bin/pygrub</bootloader>
<os>
<type>linux</type>
</os>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<devices>
<disk type='file' device='disk'>
<driver name='file'/>
<source file='/opt/lvstest1.img'/>
<target dev='sda' bus='xen'/>
</disk>
<disk type='file' device='disk'>
<driver name='file'/>
<source file='/opt/backup.img'/>
<target dev='sdb' bus='xen'/>
</disk>
<interface type='bridge'>
<mac address='00:16:3e:00:51:93'/>
<source bridge='br0'/>
<script path='/etc/xen/scripts/vif-bridge'/>
<target dev='vif1.0'/>
</interface>
<console type='pty' tty='/dev/pts/1'>
<source path='/dev/pts/1'/>
<target port='0'/>
</console>
</devices>
</domain>
4.启动VM：virsh create lvstest1.xml
5.进入系统挂载备份块：mount /dev/sdb /mnt
6.使用命令进行系统备份：dump -0uf /mnt/backup0.dump /
还原步骤：
1.把VM lvstest1关闭
2.格式化lvster1.img: mkfs.ext3 lvstest1.img
3.创建另一个VM lvsserver用来挂载lvstest1.img和backup.img lvserserver.xml配置文档如下：
<domain type='xen' id='-1'>
<name>lvsserver</name>
<uuid>a6603e99-fe0b-40bb-a076-aa56464f228f</uuid>
<memory>8388608</memory>
<currentMemory>524288</currentMemory>
<vcpu>1</vcpu>
<bootloader>/usr/bin/pygrub</bootloader>
<os>
<type>linux</type>
</os>
<clock offset='utc'/>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>restart</on_crash>
<devices>
<disk type='file' device='disk'>
<driver name='file'/>
<source file='/opt/lvsserver.img'/>
<target dev='sda' bus='xen'/>
</disk>
<disk type='file' device='disk'>
<driver name='file'/>
<source file='/opt/lvstest1.img'/>
<target dev='sdb' bus='xen'/>
</disk>
<disk type='file' device='disk'>
<driver name='file'/>
<source file='/opt/backup.img'/>
<target dev='sdc' bus='xen'/>
</disk>
<interface type='bridge'>
<mac address='00:16:3e:00:50:93'/>
<source bridge='br0'/>
<script path='/etc/xen/scripts/vif-bridge'/>
<target dev='vif1.0'/>
</interface>
<console type='pty' tty='/dev/pts/1'>
<source path='/dev/pts/1'/>
<target port='0'/>
</console>
</devices>
</domain>
3.启动VM lvsserver，进入系统
4.把sdb分区成：/dev/sdb1
5.创建挂载目录：mkdir /backup
6.挂载磁盘：
mount /dev/sdb1 /mnt
mount /dev/sdc /backup
cd /mnt
7.还原系统：restore -rvf /backup/backup0.dump
8.关闭VM lvsserver，并启动lvstest1验证系统是否正常启动。