Hi Ranjan.
For ISO images I can't dd on an usb stick I use Unetbootin[1]. It is in the Fedora repos and easy to use but has no command line interface. I have been trying to dd Ubuntu on an usb key but I doesn't work…
[1]http://unetbootin.sourceforge.net/
Regards,
Laurin
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Laurin Novak
Member Of The Fedora Localization Project - German Translators Team (https://fedoraproject.org/wiki/L10N_German_Team)
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