Creating CD-ROM ISO image in Linux

dd is a perfect tool for copy a file, converting and formatting according to the operands. It can create exact CD-ROM ISO image.

This is useful for making backup as well as for hard drive installations require a working the use of ISO images.
How do I use dd command to create an ISO image?

Put CD into CDROM

Do not mount CD. Verify if cd is mounted or not with mount command:

# mount

If cd was mouted automatically unmout it with umount command:

# umount /dev/cdrom

OR

# umount /mnt/cdrom

Create CD-ROM ISO image with dd command:

# dd if=/dev/cdrom of=/tmp/cdimg1.iso

Where,

* if=/dev/cdrom: Read from /dev/cdrom (raw format)
* of=/tmp/cdimg1.iso: write to FILE cdimg1.iso i.e. create an ISO image

Now you can use cdimg1.iso for hard disk installation or as a backup copy of cd. Please note that dd command is standard UNIX command and you should able to create backup/iso image under any UNIX like operating system.