Showing posts with label CD. Show all posts
Showing posts with label CD. Show all posts

Wednesday, 14 July 2010

Clonezilla - A free easy to use disk imaging program

If your PC operating system becomes corrupt it can be a pain to reinstall it all over again. This is why disk images are so beneficial. With a disk image you can restore your operating system in minutes.

You may have heard of Symantec Ghost or Acronis True Image, both of which are good disk imaging programs but Clonezilla not only does a good job but is free.

I have heard about Clonezilla for a long time but never used it until today.


It doesn't have a nice graphical user interface and does have a few limitations but it is very straight forward and simple.

I decided to try it out on my Samsung R510 Laptop which has Windows Vista Home Premium 64-bit installed.

Clonezilla runs from a Live CD and allows you to clone a disk to another disk or a disk to an image file.

There are also further options, for example cloning the entire disk or just a partition.

In my case I was interested in cloning the entire disk.

Clonezilla is so easy to use that it is just a case of hitting the enter button a few times. Generally all you have to do is select clone disk to image, then select where to save the image and finally which disk to clone. That is more or less it.

What I liked about Clonezilla was after I chose to save to a local disk, the program instructed to plug in any USB storage devices and hit the enter button.

So at this point I plugged in my external USB 250GB disk which features an NTFS filesystem and followed the on screen instructions.

The total disk space in use on my Samsung R510 was identified by Clonezilla as 23.9GB, which took about 12 minutes to clone to an image file on my external USB NTFS formatted drive.

Clonezilla was able to clone the drive to an image with a file size of 6.99GB which is about 30% of the used disk size, not bad.

In contrast to Acronis True Image, Clonezilla does not create a single image file.

It creates multiple files with the main drive data broken up into 2GB chunks although you can alter this by changing the expert settings.

Below is a screenshot showing the contents of my Clonezilla image. The Clonezilla program created a folder on my external USB drive called 2010-07-14-16-img, the screenshot shows the contents of that folder.

By default the 2GB max file size results in 4 main disk data files as can be seen

So if I had changed the expert settings to create 8GB file chunks, rather than 4 main data files I would have had only 1.

Unfortunately Clonezilla is not able to burn directly to CD's / DVD's or restore from CD's / DVD's.

You could burn the image files later on to a DVD for safe keeping, it is always good to have more than one backup.

Restoring the image files created by Clonezilla took about 25 minutes and was successful.

Does 25 minutes sound too long?

Well, I would rather restore an image in 25 minutes than install Windows Vista, then SP1, then SP2, then do a Windows Update followed by downloading and installing various drivers and programs. All that would take a few hours.

So if you want a free disk imaging program, try out Clonezilla.

Wednesday, 31 March 2010

How to create your Linux installation CD / DVD in Windows

After downloading a Linux distribution of your choice the next major step is to create the installation CD or DVD.

You will more than likely have downloaded a disc image (*.iso) file which needs to be burnt to a CD or DVD and is a simple process.

However even the most simplest of tasks can have complications caused by a number of factors, for example a corrupted download, poor CD / DVD media, a rubbish DVD writer drive or poor burning software.

I have in the past encounted issues as a result of a poor DVD Writer I once had, an NEC ND-2510A which has to be the worse optical drive I have ever owned. It has created more frisbees than discs.

For the past fews years I have been using a Sony AW-G170A DVD Writer optical drive and it has been extremely reliable. I have yet to have a burn go wrong.

A very common cause of corrupted installation media is due to using very cheap unbranded poor quality discs. Good quality discs are cheap enough anyway, so stay away from these silver frisbees!

Verify your downloaded disc image before burning it

It is sometimes a good idea to verify your downloaded disc image before burning it to make sure it is not corrupt or modified.

You may notice an MD5 or SHA1 checksum is provided for your download.

If the MD5 / SHA1 checksum of the file you have downloaded does not match the MD5 / SHA1 checksum listed, it simply means you have a different file.

How to find the MD5 or SHA1 of a file?

I use this cool utility called HashTab, it is available from

Once installed, right click on the file you wish to check and select properties. Then click on the tab labelled 'File Hashes'

Note: The Hash Values in this picture are for illustrative purposes only!

Burning your Linux disc image

Use your favourite image burning software or if you do not have one here are two very good free programs that I would recommend.


Launch ImgBurn > write image file to disc > select the file > click on write


Launch CDBurnerXP > Burn ISO iamge > select your file > Burn disc

Disc Image burning FAQ's

Q. I created a disc but during installation it is reported as being corrupted and fails.

A. Try burning at a lower speed, for example if your disc media is rated at 16x try 8x. This will result in a better burn. Alternatively try a different brand disc or if using a RW use a R.

Q. My Optical writer has trouble reading / writing the majority of DVD-R and DVD+R discs.

A. Try updating your optical drive's firmware. If that fails, maybe its time for a newer drive.

Q. Should I use DVD-R or DVD+R?

A. Doesnt matter, but generally DVD-R is more widely used.

Q. Is it ok to use Re-Write (RW) discs instead of Write once (R) discs?

A. Yes but the write speed of most RW discs is significantly slower than R discs and you may also encounter further issues with RW discs, for example other optical drives apart from the original used to create the disc may have difficulty reading the disc you created.

Compatibility with RW discs is still an issue. Given the price, write speed and above issues, I would suggest to stick to R discs only for better reliability.

Q. I know my Optical drive and DVD media are good but the installation says the media is corrupt.

A. Try the some of the above recommendations and also verify the downloaded disc image by comparing the md5 checksum / SHA1 or GPG key.

Use a different burning program such as ImgBurn.  

Alternatively try a different Optical drive, get someone else to burn the disc. If it works, your "I know my Optical blabla bla works" could be nothing more than a bad assumption.