Linux® For Dummies®, 8th Edition

System Control

These commands provide systemwide information and control. Normal users can run many commands to obtain system information; however, commands that actively change the configuration of the system need to run while you’re logged in as root — or have utilized the su command to temporarily become the superuser.

Administration

Some administration commands, shown in Table A-10, don’t fall neatly into a category.

Table A-10. Administration Commands

Command	Purpose
passwd	Change a particular user’s password. Any user can run this command to change their own password. Only root can use it to change someone else’s.
su	Switch to another user account without logging out of this one. The best way to use this command is su - so your filesystem path and other information is loaded.

Kernel module handling

You may sometimes need to add kernel support for an additional device (software or hardware). If this need arises, you have a limited number of choices: You can either rebuild the kernel or install a loadable kernel module. Although rebuilding a kernel doesn’t exactly require a PhD in nuclear science, consider it a time-consuming nuisance that’s best to avoid. The commands in Table A-11 enable you to include the kernel support you need while the system is running, without having to rebuild the entire thing from scratch.

Table A-11. Kernel Support Commands

Command	Purpose
depmod	Regenerates your module dependencies.
insmod	Loads a module by hand.
lsmod	Lists the modules your kernel has loaded. ...