/sbin/reboot do not shutdown the system, it writes only the warning message and kills some services. A second try usually shutdown the system. A similar problem is with /sbin/poweroff : it disables the login and most of the services, but do not switch off the computer (e.g. ping gets answers from the host) These two problems are observed, if rebooting or shutting down through the net. At the console they usually work. Peter
This was changed in 6.0; halt shuts down the network interfaces, and it tries to power off the computer, if available.