1. Linux Basic
Login Screen-
1. two types of login screens:
graphical login (called display manager)
2. login using login name and password
3. each user has a home directory for personal file storage.
Switching between virtual console and graphical environment-
1. A linux system will run six virtual consoles and one graphical console.
2. server system often have only virtual consoles
3. desktop system and workstation typically have both.
4. switch among virtual consoles by pressing:Ctrl+Alt+F[1-6]
5. access the graphical console by pressing Ctrl+Alt+F7
Elements of the X Window System-
1. the X Window System is Linux graphical subsystem
2. Xorg is the particular version of the X Window System used by Red Hat.
3. look and behavior largely controlled by the desktop environment
4. two desktop environment provided by Red Hat:-
GNOME (GNU Network Object Model Environment )
Difference Between Gnome and KDE Desktop-
Gnome
|
KDE
|
Gnome
IMO is better looking. All it is is just a different desk top
environment.
|
KDE
is lighter on resources but looks a bit more like that "Other"
operating system.
|
Note- Basically Linux Server Uses Virtual Console.
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2. Virtual Console
A virtual console (VC) – also known as a virtual terminal (VT) – is a conceptual combination of the keyboard and display for a computer user interface. It is a feature of some operating systems such as BSD, Linux, and UnixWare in which the system console of the computer can be used to switch between multiple virtual consoles to access unrelated user interfaces. Virtual consoles date back at least to Xenix in the 1980s.
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3. The
root user
2.
also called superuser
3.
root has near complete control over the system
4.
and a nearly unlimited capacity to damage it.
5.
do not login as root unless necessary
6.
normal users potential to do damage is more limited.
[root@localhost ~]#
Difference between a normal user and a root user in Linux?
Root User
|
Normal User
|
A
"root" user has the power to do anything on a Linux
system.
|
A
normal user can only gain root access with sudo if they are in the
sudoers file
|
Control all over system
|
N
|
[root@localhost
~]#
|
[uesr@localhost
~]$
|
For Example-
Admin
control all users.
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4. Basic
Command
Open
Terminal and run command-
[root@localhost
~]# whoami
Command
Description
whoami
|
Tells
the user who they are acting as; usually their own username.
|
who
|
Lists
currently logged on users username, port, and when they logged in
|
top
|
This
program shows a lot of stuff that goes on with your system. In the
|
pwd
|
Prints
the current working directory
|
ps
|
Lists
all current running processes, their corresponding pids, and their
status
|
ls
|
Lists
all information on all files
|
Ifconfig
|
This
will display the status of the currently defined interface (.e.g
#ifconfig eth0)
|
hostname
|
Get
or set hostname
|
clear
|
This
will clear your screen
|
cd
|
Changes
directories (.e.g #cd /home/dsoneil )
|
mkdir
|
This
will create new directory (.e.g. #mkdir dirname )
|
cat
|
Create
file (.e.g. #cat > filename ) create
(.e.g.
#cat < filename ) open
|
cp
|
Copy
File (.e.g. #cp file1 /root/Desssktop )
|
rm
|
Remove
File (.e.g. #rm file1 )
|
su
|
This
will allow you to access the Superuser privileges. Type exit to
revert back to normal (.e.g. #su user1 )
|
cal
|
|
date
|
Display
date
|
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