Replace the example files with the real file names. Step 3: Finally input this command to convert DMG to ISO ( dmg2img demo.dmg demo.iso) Step 2: After the package installed sucessfully, then input this command to install the package ( sudo apt-get install dmg2img) Step 1 : Lanuch Terminal app and update the system via this command ( sudo apt-get update) dmg file to ISO with a set of text commands. Actually, there is a package called dmg2img, which is able to convert. All apps are distributed in open source license, meaning you don't need to pay a single peny to use the app. The best thing about Linux is that you can complete a lot of tasks totally for free.