Disk image

A dump or disk image (just copy, english image) is an image of a disk, or data memory, which - can be stored in a file - for example, a RAM, a hard drive, partition, floppy disk, CD / DVD or a magnetic tape.

Technology

In contrast to a simple data backup an image also contains information about the (file system ) structure of the original volume, including the boot sector, since the raw data are read and not just the files. This makes it possible to quickly produce accurate and also complete copies of a disk. The high speed at which an image can be produced, derives from the ability to directly access hardware functions to read or write data. A dump file reproduces the original data carriers very closely; Some error information is copied, so that for example the image of a CD is not useless by copy protection mechanisms. Some installed software is no longer running due to copyright protection mechanisms when it is located by simply copying it back to the program files to another disk sector than in the installation. In a recovery test with a file -based backup, this software would no longer work.

If you want to duplicate CDs or on multiple computers with the same initial programs or data, you are well advised this to a CD or to create disk image, and then to write several times. It can initially be a computer completely set up this way and the hard disk are then "cloned " on the hard drives of other computers.

However, the direct terms of hardware structures can also prove to be a disadvantage - the image of a hard disk can usually not 1:1 write to a CD because the file systems of hard disks and CDs usually are completely different. In addition, image files can be read on some operating systems only with special programs and not always change; other operating systems, in turn, contain functions for working with image files as an integral part.

In particular CD image functions are usually already provided with the operating system because the non- modifiable file system ISO 9660 is very widespread. Occasionally, ISO images, the speech - so are images of CDs in ISO 9660 format meant.

Creation software

Windows

  • " Create a system image " - included since Windows 7 comes with the operating system
  • Clonezilla - open source (open source)
  • DriveImage XML - free of charge (freeware)
  • ImgBurn - free
  • Symantec / Norton Ghost - commercially
  • ODIN - open source
  • VirtualBox - commercially

Unix, GNU / Linux

  • Clonezilla (open source)
  • Dd ( part of Unix and similar systems )
  • ISO Master ( open source )
  • Partimage ( open source )

Other

  • Clonezilla (open source)
  • Mac OS Disk Utility ( Disk Utility )
Computer memory Ghost (Software) Utility software
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