Everything you wanted to know about Disk cloning - the advantages, best practices and available software.

DI reader Vinod Nair is searching for a tool to create a mirror replica of his hard-drive that can easily restore all program files, documents, data and other custom settings in the event of a hard-disk crash.

Vinod knows that popular disk backup and cloning software like Acronis True Image 9 or Norton Ghost 10 already exist but he finds them too expensive and is on a hunt for a cheap or free alternative.

Why do we need a disk cloning software ?

A complete disk image can prove to be a blessing in the following three situations:

» All your digital photographs, software programs, home videos, music, hardware drivers, documents, etc are copied to another safe location. So even if your main hard-disk runs out of service, you don't loose any of those irreplacable treasures.

» When you are upgrading the hard-disk of your computer, you can just create a disk image of the original hard-disk and then migrate that disk image onto the new drive. You don't have to undergo the painful process of reinstalling the OS, all the software or migrating the documents from one hard-disk to another. It's all done by the disk imaging software.

» You are a sysadmin in a large company (with volume software licenses) and need to provide an identical development environment to all the trainees who have just been recruited.

What does a disk backup software actually do in the background ?

Most of the commercial disk imaging software can do a backup as well as clone the full hard drive. It's like taking a "snapshot" of your file system. They will create a mirror image of everything that's residing on individual partitions or the entire computer hard-disk including the operating system.

The backup is performed in an incremental fashion, running in the background without requiring you to even restart the system. The first backup may take a long time to complete but the iterative updates will be very fast.

Which are free tools for disk backup and cloning ?

 » DriveImage XML - Freeware and still feature rich disk backup and recovery software, it even lets you schedule the disc backup tasks. The disk images can be created while the drive is in use. Similarly, the images can be restored without requiring to reboot the system. The program will backup, image and restore drives formatted with FAT 12, 16, 32 and NTFS. You can also initiate the imaging process from the command line.

» Some hard drive manufacturers like Seagate, Western Digital and Maxtor provide free utilities to their customers for cloning the old hard-drive and and transferring the image to the new disk.

» HD Clone - The HDClone Free Edition supports IDE/ATA/SATA hard disks and is intended for home users. There are no limitations except on the data copy limit which is restricted to 300 MB per minute. Besides copying complete drives, it is also possible to apply it to certain partitions only.

» Ranish Partition Manager - This is particularly useful if you have more than one operating system on a PC since it supports Linux, Windows, FreeDOS and FreeBSD. Ranish has a command line interface and it simulates disk partitioning using large files before working on the real hard drive partition tables. With Ranish, you can copy, move, and resize existing disk partitions. No fancy GUI here.

When should I run the disk backup utility ?

If you have too much data on your computer, the cloning process may take a long time to complete. You may want to run a disc clean utility like CCleaner that deletes all the temp files, empties the recycle bin folder, clear internet files, recent document history, installation files, etc so that the size of data to be copied is reduced atleast by a couple of megabytes.

But the best approach would be take a disk image immediately after installing the OS and the necessary software. You can also run the Windows Update and Office update to patch your OS before backing them up.

Be safe than sorry: Hard disk disaster can strike anyone anytime. Make sure you take regular backups of all your digital assets before anything hits you.