嵌入式硬盘录像机录像的磁盘，linux下无法挂载

Linux系统下新增一块500G磁盘，这个磁盘是用于嵌入式硬盘录像机录像的磁盘，我需要把里面的内容COPY出来，但是无法挂载这块磁盘。用fdisk -l出现如下提示：


Disk /dev/sda: 500.1G,500107862016 bytes
255 heads,63 sectors/track,60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes


Disk /dev/sda doesn't contain a valid partition table


请各位帮忙分析下。谢谢！