It won't happen to you of course, but with this tip you can probably help somebody else.
You can recover from a lost root passwd with the single user mode boot procedure, but I allways do it like this:
Press the factory rest buttun for at least 10 seconds.
login as root, no passwd (since the config is factory default)
rollback config 1 (the one before the load of factory default)
set the new passwd with set sysyem root-authentication plain-text-password
commit the config.
This is easier and quicker then the "formal" procedure.