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What is Linux?
Linux is an Open Source, free Operating System created by Linus Torvalds.
What is the linux kernel?
The Linux kernel is the core of the Linux operating system. To find out which version of the Linux kernel you are running, simply type uname -r in a terminal. For more information on the Linux kernel, please visit *www.kernel.org
What distribution of Linux should I install?
One of the pleasures of running linux is choice. The choice of which Linux Distribution you wish to run is 100% up to you. You can browse our Distributions Page for comparisons of thevarious distributions out there. If you are totally new to linux we suggest you start off with either Fedora core Linux or Mandrake Linux or ubuntu linux as they are easier to install, configure and maintain.
Who is the root user?
The root user is the master user or systems adminstrator of the machine. The root user has full access to all files and directories, which is why you will only want to use the root account to perform system maintainance or to install applications.
How do I reboot my machine?
In order to reboot your machine, you must instruct the Linux kernel to stop all the processes (programs) it's currently running. Do not simply press the reboot button on the front of your computer case, as Linux must be properly shut down/restarted. To restart your machine, as root, run either of the following commands in a terminal:
reboot
On most systems you can also press (all at once) the control, alt and delete keys.
How do I shut down my machine?
In order to shut down your machine, you must instruct the Linux kernel to stop all the processes (programs) it's currently running. Do not simply press the power off button on the front of your computer case, as Linux must be properly shut down/restarted. To shut down your machine, as root, run either of the following commands in a terminal:
halt
How do I add a user?
While logged in as root, type
at the shell prompt, replacing username with the name you want to use to log in. You can create as many users as you wish, one for each member of your family, for example.
How do I delete a user?
While logged in as root, type
at the shell prompt, replacing username with the user name you wish to delete.
How do I change my login password?
To set the password for a specific user, type (while logged in as root)
e at the shell prompt, replacing username with the name of the person who's password you wish to change. By typing just passwd you'll be able to change the password of the user under who's name you're currently logged in as. Do not use passwords which are easy to guess, like your middle name or your pets name.
How do I change directories?
Usage: cd [directory]
Example: cd /home/joey/html
Example: cd ../ (to move back one directory)
Example: cd (to return to your home directory)
For more information, in a terminal, type man cd
How do I copy files?
Usage: cp file newlocation
Example: cp /home/joey/index.html /var/www/index.html
Example: cp /home/joey/* /var/www/ (this will copy everything in /home/joey to /var/www/)
For more information, in a terminal, type man cp
How do I move files?
Usage: mv file location (to move)
Usage: mv filename newfilename (to rename)
Example: mv index.html /var/www/index.html (to move)
Example: mv index.html index2.html (rename)
For more information, in a terminal, type man mv
How do I edit files?
The default editor that ships with almost every distribution of Linux is Vi. This editor is slightly advanced and confuses most newbies. We suggest starting off with nano, a more simple editor. It might already be installed on your system. To edit a file with nano, simply run:
This will open up the file and allow to you edit it. At the bottom of the screen you will notice the various commands that you have access to with nano. If you wish to save the file and exit, simply hold down the control key and hit the x key on your keyboard.
How do I list directory contents?
- To list the contents of a directory
Usage: ls [flags] directory
Example: ls (To list the current directory)
Example: ls /home/joey (To list the contents of /home/joey)
Example: ls -a (To list hidden files)
Example: ls -l (To list file/directory permissions and file sizes)
Example: ls -al /home/joey (To list all files and permissions in /home/joey)
For more information, in a terminal, type man ls
How do I delete files?
To delete a file you must first have write permission to it. For information about permissions, click here. Once you have write permission, in a terminal run:
There is no "Recycle Bin" in Linux so once you delete a file, it's gone for good.
When removing files, you may use an astrix (*) as a wildcard flag to remove certain files, for example if I wanted to remove all files that began with the letter j, I would run rm j*
If anyone tells you to run rm -rf / as root, DO NOT LISTEN TO THEM. Running this command will delete all the files/directories on your Linux system.
How do I delete directories?
If you have ownership to the directory and the directory is empty, you can simply type
to remove the directory. If the directory is not empty and you wish to simply delete it and all its contents, run
Please be careful with the -rf flag, as it will remove everything in the specified directory including sub directories. With root access and the rm -rf command you can wipe out your entire system if you make an error.
How do I access my cdrom drive?
Linux requires you to mount your cdrom/floppy drives when you wish to use them. On most Linux distributions, the mount command will require root access. Depending on which Linux distribution you run, one of the following commands should mount your cdrom drive. As root, run:
How do I access my floppy drive?
Linux requires you to mount your cdrom/floppy drives when you wish to use them. On most Linux distributions, the mount command will require root access. Depending on which Linux distribution you run, one of the following commands should mount your floppy drive. As root, run:
How do I view/change ownership on files/directories?
One of the great features of Linux is that it is a multi-user system. With multi-users, it allows certain users to own files and directories so nobody else can access/modify them, for example your /home directory. To change the ownership of a file/directory, as root execute the following command in a terminal:
This will change the ownership and group ownership of the specified file or directory to the specified user. For more information, in a terminal, type man chown
How do I view/change permissions on files/directories?
There are 3 different attributes a file can have that make up the permissions for the file.
There is read access that allows users to read the file.
There is write access that allows users to modify the file.
There is executable access that allows users to execute the file.
From these three attributes, you now have three different levels of permissions, the first being for the owner of the file, the second being for the group the file belongs to and the third being all other users on the system.
To view the current permissions on files and directories run the following command:
ls -l and you should see something that looks like:
drwxrwxr-x 3 joey html 4096 Sep 12 2000 images/
-rw-rw-r-- 1 joey html 267 Aug 8 12:55 index.shtml
The above shows you that images is a directory (d) and that the owner and group (joey html) have read ?, write (w) and execute (x) permissions while other users on the system only have read ? and execute (x) permissions.
For the index.shtml file, it shows joey and html as the owner and group and they both have read and write access to the file. It also shows that other users on the system only have read access. Note there is no executable permission since the file is not an executable.
To modify the permissions on a file, you either have to own it or be logged in as root. To modify the permissions, in a terminal type:
You will have to replace the xxx flags with the permissions you wish to change. You can either go by the numerical value or by the actuals.
Some common numerical values are:
755 - Read, Write, Execute for owner, read, execute for group and other.
644 - Read, Write for owner, read for group and other.
666 - Read, Write for all.
700 - Read, Write, Execute for owner, nothing for group, other.
So if you wanted to make a file an executable for your user and other users on the system, you would run the following:
chmod 755 somefile
For more information, in a terminal, type man chmod
How do I find files on my system?
There are two methods to search for files on your Linux machine, one method being the locate command and the other being the find command. If you wish to use the locate command, you must first update the locate database by running the following command in a terminal as root:
This will create an index of all the files and their locations on your hard drive. Once updatedb has completed running, you may now search your drive for a specific file by running the following command in a terminal:
Another way to search your linux system is with the find command. To find a file on your sytem with the find command, in a terminal run the follwoing:
Be sure to replace "filename" with the actual name of the file.
How do I unzip a .tar.gz/.tgz file?
To extract .tar.gz or .tgz files, run the following command in a terminal:
(or file.tgz)
This will normally create a new directory based on the filename. If you want to extract a filename called file.tar (without the .gz) simply run:
For more information, in a terminal, type man tar
How do I unzip a .bz2 file?
To extract .bz2 files, run the following command in a terminal:
This will normally create a new directory based on the filename. For more information, in a terminal, type man buznip2
How do I install a program?
There are many ways to install applications in Linux. If the file you wish to install is in .rpm format and you are running an RPM based distribution such as Red Hat, Mandrake or SuSE, run the following command as root in a shell prompt/terminal:
If you are running Debian GNU/Linux and you wish to install a .deb file, you can do so by running the following command in a terminal as root:
or
(if you have APT already installed/configured).
If the file you with to install is in a .tar.gz, .tgz or .bz2 format, you will first have to decompress (unzip) the file. Once the file has been unziped, it should create a directory based on the filename. Simply change into that directory and open up the README or INSTALL file in a text editor and follow the installation instructions.
How do I run a program?
To run a program, you must first make sure it has executable permissions set. For more information on permissions, see How do I view/change permissions on files/directories? above. Once the file has executable permissions, simply run the filename from a terminal. I will use the filename "irc" as an example
Example:
(from anywhere on the system)
Example: ./irc (from the /usr/bin directory)
source
What is the linux kernel?
The Linux kernel is the core of the Linux operating system. To find out which version of the Linux kernel you are running, simply type uname -r in a terminal. For more information on the Linux kernel, please visit *www.kernel.org
What distribution of Linux should I install?
One of the pleasures of running linux is choice. The choice of which Linux Distribution you wish to run is 100% up to you. You can browse our Distributions Page for comparisons of thevarious distributions out there. If you are totally new to linux we suggest you start off with either Fedora core Linux or Mandrake Linux or ubuntu linux as they are easier to install, configure and maintain.
Who is the root user?
The root user is the master user or systems adminstrator of the machine. The root user has full access to all files and directories, which is why you will only want to use the root account to perform system maintainance or to install applications.
How do I reboot my machine?
In order to reboot your machine, you must instruct the Linux kernel to stop all the processes (programs) it's currently running. Do not simply press the reboot button on the front of your computer case, as Linux must be properly shut down/restarted. To restart your machine, as root, run either of the following commands in a terminal:
reboot
Code:
shutdown -r nowHow do I shut down my machine?
In order to shut down your machine, you must instruct the Linux kernel to stop all the processes (programs) it's currently running. Do not simply press the power off button on the front of your computer case, as Linux must be properly shut down/restarted. To shut down your machine, as root, run either of the following commands in a terminal:
halt
Code:
shutdown -h nowHow do I add a user?
While logged in as root, type
Code:
adduser usernameHow do I delete a user?
While logged in as root, type
Code:
userdel usernameHow do I change my login password?
To set the password for a specific user, type (while logged in as root)
Code:
passwd usernamHow do I change directories?
Code:
cd - Used to change directoriesExample: cd /home/joey/html
Example: cd ../ (to move back one directory)
Example: cd (to return to your home directory)
For more information, in a terminal, type man cd
How do I copy files?
Code:
cp - Used to copy files/directories from one location to anotherExample: cp /home/joey/index.html /var/www/index.html
Example: cp /home/joey/* /var/www/ (this will copy everything in /home/joey to /var/www/)
For more information, in a terminal, type man cp
How do I move files?
Code:
mv - Used to move or rename filesUsage: mv filename newfilename (to rename)
Example: mv index.html /var/www/index.html (to move)
Example: mv index.html index2.html (rename)
For more information, in a terminal, type man mv
How do I edit files?
The default editor that ships with almost every distribution of Linux is Vi. This editor is slightly advanced and confuses most newbies. We suggest starting off with nano, a more simple editor. It might already be installed on your system. To edit a file with nano, simply run:
Code:
pico filenameThis will open up the file and allow to you edit it. At the bottom of the screen you will notice the various commands that you have access to with nano. If you wish to save the file and exit, simply hold down the control key and hit the x key on your keyboard.
How do I list directory contents?
Code:
lsUsage: ls [flags] directory
Example: ls (To list the current directory)
Example: ls /home/joey (To list the contents of /home/joey)
Example: ls -a (To list hidden files)
Example: ls -l (To list file/directory permissions and file sizes)
Example: ls -al /home/joey (To list all files and permissions in /home/joey)
For more information, in a terminal, type man ls
How do I delete files?
To delete a file you must first have write permission to it. For information about permissions, click here. Once you have write permission, in a terminal run:
Code:
rm filenameWhen removing files, you may use an astrix (*) as a wildcard flag to remove certain files, for example if I wanted to remove all files that began with the letter j, I would run rm j*
If anyone tells you to run rm -rf / as root, DO NOT LISTEN TO THEM. Running this command will delete all the files/directories on your Linux system.
How do I delete directories?
If you have ownership to the directory and the directory is empty, you can simply type
Code:
rmdir directoryname
Code:
rm -rf directorynameHow do I access my cdrom drive?
Linux requires you to mount your cdrom/floppy drives when you wish to use them. On most Linux distributions, the mount command will require root access. Depending on which Linux distribution you run, one of the following commands should mount your cdrom drive. As root, run:
Code:
mount /dev/cdrom /mnt/cdrom
mount /dev/cdrom /cdromHow do I access my floppy drive?
Linux requires you to mount your cdrom/floppy drives when you wish to use them. On most Linux distributions, the mount command will require root access. Depending on which Linux distribution you run, one of the following commands should mount your floppy drive. As root, run:
Code:
mount /dev/fd0 /mnt/floppy
mount /dev/fd0 /floppyHow do I view/change ownership on files/directories?
One of the great features of Linux is that it is a multi-user system. With multi-users, it allows certain users to own files and directories so nobody else can access/modify them, for example your /home directory. To change the ownership of a file/directory, as root execute the following command in a terminal:
Code:
chown username. filename/directoryHow do I view/change permissions on files/directories?
There are 3 different attributes a file can have that make up the permissions for the file.
There is read access that allows users to read the file.
There is write access that allows users to modify the file.
There is executable access that allows users to execute the file.
From these three attributes, you now have three different levels of permissions, the first being for the owner of the file, the second being for the group the file belongs to and the third being all other users on the system.
To view the current permissions on files and directories run the following command:
ls -l and you should see something that looks like:
drwxrwxr-x 3 joey html 4096 Sep 12 2000 images/
-rw-rw-r-- 1 joey html 267 Aug 8 12:55 index.shtml
The above shows you that images is a directory (d) and that the owner and group (joey html) have read ?, write (w) and execute (x) permissions while other users on the system only have read ? and execute (x) permissions.
For the index.shtml file, it shows joey and html as the owner and group and they both have read and write access to the file. It also shows that other users on the system only have read access. Note there is no executable permission since the file is not an executable.
To modify the permissions on a file, you either have to own it or be logged in as root. To modify the permissions, in a terminal type:
Code:
chmod xxx filename/directorySome common numerical values are:
755 - Read, Write, Execute for owner, read, execute for group and other.
644 - Read, Write for owner, read for group and other.
666 - Read, Write for all.
700 - Read, Write, Execute for owner, nothing for group, other.
So if you wanted to make a file an executable for your user and other users on the system, you would run the following:
chmod 755 somefile
For more information, in a terminal, type man chmod
How do I find files on my system?
There are two methods to search for files on your Linux machine, one method being the locate command and the other being the find command. If you wish to use the locate command, you must first update the locate database by running the following command in a terminal as root:
Code:
/usr/bin/updatedb
Code:
/usr/bin/locate filenameAnother way to search your linux system is with the find command. To find a file on your sytem with the find command, in a terminal run the follwoing:
Code:
/usr/bin/find / -name filenameHow do I unzip a .tar.gz/.tgz file?
To extract .tar.gz or .tgz files, run the following command in a terminal:
Code:
tar -zxvf file.tar.gzThis will normally create a new directory based on the filename. If you want to extract a filename called file.tar (without the .gz) simply run:
Code:
tar -xvf file.tarHow do I unzip a .bz2 file?
To extract .bz2 files, run the following command in a terminal:
Code:
bunzip2 -dv file.bz2How do I install a program?
There are many ways to install applications in Linux. If the file you wish to install is in .rpm format and you are running an RPM based distribution such as Red Hat, Mandrake or SuSE, run the following command as root in a shell prompt/terminal:
Code:
rpm -Uvh filename.rpmIf you are running Debian GNU/Linux and you wish to install a .deb file, you can do so by running the following command in a terminal as root:
Code:
dpkg -i filename.deb
Code:
apt-get install packageIf the file you with to install is in a .tar.gz, .tgz or .bz2 format, you will first have to decompress (unzip) the file. Once the file has been unziped, it should create a directory based on the filename. Simply change into that directory and open up the README or INSTALL file in a text editor and follow the installation instructions.
How do I run a program?
To run a program, you must first make sure it has executable permissions set. For more information on permissions, see How do I view/change permissions on files/directories? above. Once the file has executable permissions, simply run the filename from a terminal. I will use the filename "irc" as an example
Example:
Code:
/usr/bin/ircExample: ./irc (from the /usr/bin directory)
source
Last edited:
