SUPERUSER, LINUX TUTORIAL, PART 44


this episode of our linux journey is about
superusers. during the course of our journey, we already
heard about users and permissions, and in our last episode, we’ve seen how a certain
root user owns files that are crucially important to the linux system. so, at this point, we have our linux system
and we like to think of it as a humungous file tree structure, right? also we have user accounts that make it possible
to manage access rights to the files of this tree. now it seams only reasonable to restrict access
to system files to admin users, so that such system files are off limits for ordinary vanilla-type
users. alright, so now on a linux system, the user
named root is normally responsible for system administration tasks, which is why, she normally
owns important utility program files, as we’ve seen. now, one may easily be fooled by her glasses
and acknowledge the root user employing a so-what-shouldershrug kind of attitude, but
underestimating root is a mistake, because hidden under the shirt there’s a cape, meaning,
the root user actually wheels the powers of a superuser, powers far in excess of those
ordinary users are endowed with. so, there’s really a forth category of users
that we should know about. namely superusers. and our flowchart illustration shows, how
all users that possess the special superuser quality, have full right to do whatever with witchever file
they please. for example if a file’s permission declares,
that it can only be read by it’s owner, this can’t hinder a superuser from reading it,
or modifying it, or whatever, because there are no limits to what a superuser can do on
a linux system. now, couple of things to note here: first, a superuser’s name need not be root. second, there can be more than one superuser
on a single system. alright, we all know the saying, that, with
great power comes great responsibility, and therefore one should only become superuser,
when the circumstances absolutely require it, simply because of the everpresent risk
of the disastrous damage that a superuser can cause with only a handful of keystrokes. as an example, consider the famous 8 characters
it takes to recursively remove all files present on the system. if a superuser is ever to execute this command,
the entire system will be utterly destroyed, no questions asked, because of the f short
option. in conclusion, warned and a bit scared, we
can now agree that having to become a superuser is a bad and unpleasant necessity of a linux-admin’s
life, but still we have to be prepared, we have to ask how to do it, how can we become
superuser if the circumstances require it. good question! let’s find out in our next
episode.