通过loop方式挂载raw格式镜像

虚拟机的镜像可以直接通过loop的方式来进行挂载，这种方式你必须先计算出镜像中每个分区的偏移量（fdisk -lu可查看），然后通过loop的方式的挂载，加上偏移量

详细命令如下

[root@centos images]# cd /var/lib/libvirt/images/
[root@centos images]# fdisk -lu ubuntu.raw 
You must set cylinders.
You can do this from the extra functions menu.

Disk ubuntu.raw: 0 MB, 0 bytes
255 heads, 63 sectors/track, 0 cylinders, total 0 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: 0x000ccae5

     Device Boot      Start         End      Blocks   Id  System
ubuntu.raw1   *        2048    38862847    19430400   83  Linux
Partition 1 has different physical/logical endings:
     phys=(1023, 254, 63) logical=(2419, 25, 38)
ubuntu.raw2        38864894    40957951     1046529    5  Extended
Partition 2 has different physical/logical beginnings (non-Linux?):
     phys=(1023, 254, 63) logical=(2419, 58, 6)
Partition 2 has different physical/logical endings:
     phys=(1023, 254, 63) logical=(2549, 131, 14)
ubuntu.raw5        38864896    40957951     1046528   82  Linux swap / Solaris
[root@centos images]# echo $((2048*512))
1048576
[root@centos images]# mount -o loop,offset=1048576 ubuntu.raw /image/
[root@centos images]# umount /image/

PS：这个方式的镜像必须是Raw格式的。

当然你也可以通过kpartx的方式进行挂载，详见 通过kpartx方式挂载raw格式镜像