Installing Ubuntu from an existing Linux
I’m giving my old laptop to my mother so that she can browse the web, write emails and chat over instant messaging and I wanted to replace Debian with Ubuntu. However, the cdrom no longer works and the mother board doesn’t support booting from an USB drive. One solution is to add an entry to your bootloader pointing to a netinstall vmlinuz (here called linux) and initrd.gz and choose that entry at boot in order to perform the netinstall. You need an Internet connection over a LAN network with a DHCP server. All the details are available here.