What to do if the user password on the virtual machine Linux is forgotten?

Once in the experiment, need to enter the Linux platform, on the public computer installed on the virtual machine on the Linux version of the Fedora 8 system, because not my computer in the system when not know the user password, so collated a bit of information, for later forget and to meet the same problem friends to provide a reference, OK, Turn to the chase.

1, open the target machine, in Grub startup, press the E-letter key, you will soon see three options, as follows:

2, continue to press the E-letter key, select Kernel/vmlinuz-2.6.21-1.3194.fc7 ro root=label=/rhgb quiet (of course, different versions of the Linux kernel version number is different, it doesn't matter, look at the back RHGB quiet Can)

3, after the addition of S, and then (enter) enter after press the B-letter key, enter the single-user mode, one will appear the following:

4, using passwd to modify the user's password you want to modify, ok! Finally, reboot a bit.

What to do if the user password on the virtual machine Linux is forgotten?