How about 'breaking' it?
if you can boot the machine, you can reset the password. This doesn't actually belong here, but I'll write this (shortly) anyway..for more information, search for the already-answered threads about resetting root password.
Route no. 1:
try to login as root with empty password, just to check if it's left empty
Route no. 2:
Boot into single user mode. With GRUB this means:
- enter the boot menu
- hilight the selection you were going to boot anyway
- press 'e' (mentioned at the bottom) to edit the entry
- hilight the line that starts with the word 'kernel' and press 'e' to edit it
- add the word 'single' among the other options in the line; usually at the end
- press ENTER and then 'b' to boot
In the end you should be logged in as root without passwords asked. Run
and change the root password.
Route no. 3:
Boot the machine with a live-cd of any Linux distribution that can read the partitions of the harddisk-installed Linux (Ubuntu uses ext3 and possibly LVM if I'm right). Mount the Ubuntu partition where passwd and shadow files are (usually root partition; /etc/shadow). From the /etc/shadow file clear the second column (columns are separated by commas; after clearing the second column should be empty, so there's just "root:
thercolumnscontinuehere". Save, umount the partition and reboot normally. If everything went all right, you should be able to log in as root with empty password..
