@Sebastian-Roth

Yes I tried the below code which you have given and it works, Many thanks.

kernel http://${fog-ip}/fog/service/ipxe/clonezilla/vmlinuz initrd http://${fog-ip}/fog/service/ipxe/clonezilla/initrd.img imgargs vmlinuz initrd=initrd.img boot=live username=user union=overlay config components quiet noswap edd=on nomodeset nodmraid locales= keyboard-layouts= ocs_live_run="ocs-live-general" ocs_live_extra_param="" ocs_live_batch=no net.ifnames=0 nosplash noprompt fetch=http://${fog-ip}/fog/service/ipxe/clonezilla/filesystem.squashfs boot || goto MENU

and yes it is all about the putting right parameters.

Regards,