[CentOS] how long to reboot server ?

>My reboot times are regular, (still on F12 on this
>machine) but I always copy the kernel files into a subdir 'tmp-backups' so I can get them back if needed, even if yum deletes them.

Huh, ok... What do you do with *just* the kernel?
Let me know how that works if you ever want to boot from it? Possibly the rpm
might make more sense?