Linux系统下对系统镜像的简单备份所用的命令就是dd命令了。
但是对备份的系统文件可能并不适合新的硬盘。
比如如下的应用环境：
1、目前在一个母板的SSD上已经安装好了一个Linux系统，并在Linux系统上部署好了具体的应用；
2、将母板上的SSD硬盘镜像备份出来，一则为了保护当前的Linux系统，防止系统损坏或丢失后的重复部署；二则可以将此份备份的镜像文件写入到另外的SSD硬盘中，克隆另外一份系统，以实现快速部署；
3、需要考虑的问题，就是母版中的网络配置。
Linux在自动加载设备硬件时，使用的是udev来协助管理系统中各设备名称。
而克隆后的文件系统，在加载到新的主板上后，系统启动时则会出现网络接口名称错乱的问题。
这个问题就是udev服务在加载时，首先加载已经存在的网络接口的的配置文件
（/etc/udev/rules.d/70-persistent-net.rules），对不对应的接口再进行设备序号的添加，
最终导致克隆后的硬盘启动后网络接口是从1或2开始排序，而不是从eth0开始。
对于这种问题，可以有两种解决方法：
第一、直接修改母板中的70-persistent-net.rules、ifcfg-eth0/ifcfg-eth1配置文件，然后备份出所需的镜像，最后再修改回去；
第二、首先备份出母板中的镜像，然后对镜像进行修改，修改成通用的
（即：注释掉所有的70-persistent-net.rules、ifcfg-eth0/ifcfg-eth1网络接口文件）。
为了不改变母板中的系统，我采用了第二种方法，具体的操作步骤及命令如下：
### 将母板中的系统镜像备份到移动硬盘中 ###
[root@localhost ~]# fdisk -l
Disk /dev/sda: 31.7 GB, 31675383808 bytes
255 heads, 63 sectors/track, 3850 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x56af7af6
Device Boot Start End Blocks Id System
/dev/sda1 * 1 64 512000 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 64 3851 30419968 8e Linux LVM
Disk /dev/mapper/VolGroup-lv_root: 28.0 GB, 27980201984 bytes
255 heads, 63 sectors/track, 3401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/mapper/VolGroup-lv_swap: 3166 MB, 3166699520 bytes
255 heads, 63 sectors/track, 384 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
[root@localhost ~]# dd if=/dev/sda of=/media/Box-20161202.img
### 卸载移动硬盘，并将移动硬盘上的母板镜像复制到其他的Linux系统中 ###
这里用的系统是ubuntu，为了方便直接通过sudo -i命令切换到了root用户
login as: leekwen
leekwen@192.168.1.180's password:
Welcome to Ubuntu 12.04.4 LTS (GNU/Linux 3.11.0-15-generic i686)
* Documentation: https://help.ubuntu.com/
New release '14.04.1 LTS' available.
Run 'do-release-upgrade' to upgrade to it.
Last login: Fri Dec 2 16:49:02 2016 from thinkpadx64.lan
leekwen@leekwen:~$ sudo -i
[sudo] password for leekwen:
root@leekwen:~# fdisk -l /dev/sdb
Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 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 identifier: 0x00055e54
Device Boot Start End Blocks Id System
/dev/sdb1 2048 629147647 314572800 83 Linux
/dev/sdb2 629147648 1258293247 314572800 83 Linux
/dev/sdb3 1258293248 1953525167 347615960 b W95 FAT32
root@leekwen:~# mount /dev/sdb2 /mnt/
root@leekwen:~# ls /mnt/
binary/ profile-tail1.txt rpmforge.list
root@leekwen:~# ls /mnt/binary/Box-20161202.img -l
-rw-r--r--. 1 root root 31675383808 Dec 2 16:42 /mnt/binary/Box-20161202.img
root@leekwen:~# cp /mnt/binary/Box-20161202.img .
root@leekwen:~# fdisk -l Box-20161202.img
Disk Box-20161202.img: 31.7 GB, 31675383808 bytes
255 heads, 63 sectors/track, 3850 cylinders, total 61865984 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 identifier: 0x56af7af6
Device Boot Start End Blocks Id System
Box-20161202.img1 * 2048 1026047 512000 83 Linux
Box-20161202.img2 1026048 61865983 30419968 8e Linux LVM
看到这行：
Device Boot Start End Blocks Id System
Box-20161202.img1 * 2048 1026047 512000 83 Linux
发现linux的文件系统是从第2048块开始的，所以挂载的时候应该从这个地方开始挂载，由这条信息可以得出，扇区大小为512
Units = sectors of 1 * 512 = 512 bytes
所以我们需要从512*2048=1048576出开始挂载
root@leekwen:~# echo $((512*2048))
1048576
root@leekwen:~# mount -o loop,offset=1048576 Box-20161202.img /mnt
root@leekwen:~# cd /mnt/
root@leekwen:/mnt# ls
config-2.6.32-431.el6.i686 initramfs-2.6.32-431.el6.i686.img initrd-3.10.28kdump.img System.map vmlinuz
efi initramfs-3.10.28.img lost+found System.map-2.6.32-431.el6.i686 vmlinuz-2.6.32-431.el6.i686
grub initrd-2.6.32-431.el6.i686kdump.img symvers-2.6.32-431.el6.i686.gz System.map-3.10.28 vmlinuz-3.10.28
root@leekwen:/mnt# ls -l
total 54082
-rw-r--r--. 1 root root 109953 Nov 22 2013 config-2.6.32-431.el6.i686
drwxr-xr-x. 3 root root 1024 Nov 24 11:41 efi
drwxr-xr-x. 2 root root 1024 Dec 2 16:13 grub
-rw-------. 1 root root 16260076 Nov 24 11:52 initramfs-2.6.32-431.el6.i686.img
-rw-------. 1 root root 17004428 Nov 25 12:26 initramfs-3.10.28.img
-rw-------. 1 root root 4730164 Nov 24 14:51 initrd-2.6.32-431.el6.i686kdump.img
-rw-------. 1 root root 4884466 Nov 25 11:06 initrd-3.10.28kdump.img
drwx------. 2 root root 12288 Nov 24 11:23 lost+found
-rw-r--r--. 1 root root 190104 Nov 22 2013 symvers-2.6.32-431.el6.i686.gz
lrwxrwxrwx. 1 root root 24 Nov 25 11:03 System.map -> /boot/System.map-3.10.28
-rw-r--r--. 1 root root 1982877 Nov 22 2013 System.map-2.6.32-431.el6.i686
-rw-r--r--. 1 root root 2075204 Nov 25 11:03 System.map-3.10.28
lrwxrwxrwx. 1 root root 21 Nov 25 11:03 vmlinuz -> /boot/vmlinuz-3.10.28
-rwxr-xr-x. 1 root root 4002656 Nov 22 2013 vmlinuz-2.6.32-431.el6.i686
-rw-r--r--. 1 root root 4106432 Nov 25 11:03 vmlinuz-3.10.28
已经挂载成功，并看到系统盘中的数据，这个ID为83直接是系统的镜像，挂载相对不复杂。
而系统镜像Box-20161202.img2的格式却是LVM格式，这个系统的挂载就需要借助于工具了。
root@leekwen:~# echo $((512*1026048))
525336576
root@leekwen:~# losetup /dev/loop0 Box-20161202.img -o 525336576
无pvscan命令，需要安装lvm2工具进行挂载：
root@leekwen:~# pvscan
The program 'pvscan' is currently not installed. You can install it by typing:
apt-get install lvm2
root@leekwen:~# apt-get install lvm2
上面是安装lvm2工具
root@leekwen:~# pvscan
PV /dev/loop0 VG VolGroup lvm2 [29.01 GiB / 0 free]
Total: 1 [29.01 GiB] / in use: 1 [29.01 GiB] / in no VG: 0 [0 ]
root@leekwen:~# vgchange -ay
2 logical volume(s) in volume group "VolGroup" now active
root@leekwen:~# mount /dev/mapper/
control VolGroup-lv_root VolGroup-lv_swap
root@leekwen:~# mount /dev/mapper/VolGroup-lv_root /mnt/
root@leekwen:~# cd /mnt/
root@leekwen:/mnt# ls -l
total 124
dr-xr-xr-x. 2 root root 4096 Nov 28 09:27 bin
drwxr-xr-x. 2 root root 4096 Nov 24 11:24 boot
drwxr-xr-x. 2 root root 4096 Nov 24 11:24 dev
drwxr-xr-x. 120 root root 12288 Dec 2 16:20 etc
drwxr-xr-x. 3 root root 4096 Nov 24 12:32 home
dr-xr-xr-x. 18 root root 12288 Nov 28 09:27 lib
drwx------. 2 root root 16384 Nov 24 11:23 lost+found
drwxr-xr-x. 5 root root 4096 Dec 2 16:20 media
drwxr-xr-x. 2 root root 4096 Nov 23 2013 misc
drwxr-xr-x. 2 root root 4096 Sep 23 2011 mnt
drwxr-xr-x. 2 root root 4096 Nov 23 2013 net
-rw-r--r--. 1 root root 0 Nov 25 11:47 null
drwxr-xr-x. 4 root root 4096 Dec 2 15:33 opt
drwxr-xr-x. 2 root root 4096 Nov 24 11:24 proc
-rw-r--r--. 1 root root 137 Dec 2 15:38 profilerc
dr-xr-x---. 34 root root 4096 Dec 2 16:31 root
dr-xr-xr-x. 2 root root 12288 Nov 28 09:27 sbin
drwxr-xr-x. 2 root root 4096 Nov 24 11:25 selinux
drwxr-xr-x. 2 root root 4096 Sep 23 2011 srv
drwxr-xr-x. 2 root root 4096 Nov 24 11:24 sys
drwxrwxrwt. 33 root root 4096 Dec 2 16:15 tmp
drwxr-xr-x. 12 root root 4096 Nov 24 11:25 usr
drwxr-xr-x. 22 root root 4096 Nov 24 11:50 var
注释掉母板中的配置
root@leekwen:/mnt/etc/udev/rules.d# cat 70-persistent-net.rules
# This file was automatically generated by the /lib/udev/write_net_rules
# program, run by the persistent-net-generator.rules rules file.
#
# You can modify it, as long as you keep each rule on a single
# line, and change only the value of the NAME= key.
# PCI device 0x10ec:0x8168 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:18:7d:a5:35:31", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
# PCI device 0x10ec:0x8168 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:18:7d:a5:35:32", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
root@leekwen:/mnt/etc/udev/rules.d# vim 70-persistent-net.rules
root@leekwen:/mnt/etc/udev/rules.d# cat 70-persistent-net.rules
# This file was automatically generated by the /lib/udev/write_net_rules
# program, run by the persistent-net-generator.rules rules file.
#
# You can modify it, as long as you keep each rule on a single
# line, and change only the value of the NAME= key.
# PCI device 0x10ec:0x8168 (r8169)
#SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:18:7d:a5:35:31", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
# PCI device 0x10ec:0x8168 (r8169)
#SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="00:18:7d:a5:35:32", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"
查看母板中的网络接口配置文件：
root@leekwen:/mnt# cat etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
HWADDR=00:18:7D:A5:35:31
TYPE=Ethernet
UUID=c1843b9a-490a-46f6-87c9-bc734d016f9d
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
root@leekwen:/mnt# cat etc/sysconfig/network-scripts/ifcfg-eth1
DEVICE=eth1
HWADDR=00:18:7D:A5:35:32
TYPE=Ethernet
UUID=ac6f78b1-f75e-4ba4-b379-5b9353ad008d
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
修改网络接口配置文件，如下：
root@leekwen:/mnt# cat etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
#HWADDR=00:18:7D:A5:35:31
TYPE=Ethernet
#UUID=c1843b9a-490a-46f6-87c9-bc734d016f9d
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
root@leekwen:/mnt# cat etc/sysconfig/network-scripts/ifcfg-eth1
DEVICE=eth1
#HWADDR=00:18:7D:A5:35:32
TYPE=Ethernet
#UUID=ac6f78b1-f75e-4ba4-b379-5b9353ad008d
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
卸载挂载、激活的LVM分区：
root@leekwen:~# vgchange -an VolGroup
0 logical volume(s) in volume group "VolGroup" now active
root@leekwen:~# losetup -d /dev/loop0
root@leekwen:~#
按照上述步骤，系统修改完成了。
下步操作就是直接将目前的修改好的这个镜像，写入到新的SSD硬盘上。
1、linux系统下就用dd命令了；
2、windows下就可以用Win32DiskImager.exe，自己写入吧，这里就不赘述了。