Lecture1.Course Content Schedule Grading Course References Introduction to Linux

8/18/2019 Lecture1.Course Content Schedule Grading Course References Introduction to Linux

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LINUX SYSTEM AND

NETWORK ADMINISTRATION

RHCSA/RHCE


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Module I

Course Content

Lecture/Lab 1 – Introduction to UNIX

- UNIX Operating System Architecture – Linux Operating System – Users, Groups and Permissions

- Examining PermissionsLecture/Lab 2 – Linux Installation – Hard Disk Partition Details – Linux File System

- ext2 / ext3 – Dual Boot Installation

Lecture/Lab 3 – Desktop Familiarization

- Text and GUI Mode - Virtual Terminals- GNOME and KDE Desktop


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Module I

Course Content

Lecture/Lab 4 & 5 – UNIX Shell – UNIX Commands – Shell Commands

- File System Management - File Management and Viewing

- Help, Job and Process Management

- Network Management- System Management- User Management

- Printing and Programming- Document Preparation

- MiscellaneousLecture/Lab 6 – System Initialization and Services

- Boot Sequence, Runlevels & Daemon Processes – User Administration

- User Creation/ Suspension & Deletion

- Group Administration


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Module ICourse Content

Lecture/Lab 7

–Network Configuration

- Configuration Utilities

- Multiple NICs – Task Schedulers

- cron daemons – Disk quota management – Backup and Restore

Lecture/Lab 8 – Adding and Removing Software Packages

• RPM Package Management – Setting Printer – System Monitoring

- File System Analysis

- System Log Files & Analysis – System Troubleshooting

- Filesystem Corruption and Recovery

- Things to check: The X Window System

- Service, Networking & Booting

- The Rescue Environment

- Recovery Runlevels, Boot Floppies


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Module II

Course Content

Lecture/Lab 9 – DHCP

- Server setup- Client setup

– NIS- NIS Server setup

- NIS Client setup

Lecture/Lab 10 – NFS

- NFS Server & Client configuration - autofs implementation

– Samba Server - File & Print Service

Lecture/Lab 11 – Basic Concept of DNS

- Implementation of BIND

- forward & reverse lookup

- DNS Directives


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Module II

Course Content

• Lecture/Lab 12 – Apache Web Server

- Basic Configuration

- Name based Virtual Hosting

- Restriction through htaccess

• Lecture/Lab 13 – Sendmail - Mail Server

- Configuring mail service - SMTP Server• POP3 / IMAP Server

• Lecture/Lab 14

– Proxy Server - Squid

- ACL for restricting access

• Lecture/Lab 15 – Linux System as a Router

- Setup and configuration

- Static Routing – SELinux Configuration – Firewall Using IPTables

- Filter and NAT rules


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Course Schedule

Schedule

The complete course, including Lectures andLabs, will be covered in 60 Hours.

The total duration of the course will be 3.5 - 4months.

Lectures : Every Tuesday, 17:00 – 18:30 P.M

Labs : Thursday late, 18:30 – 20:00 P.M


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Grading Guidelines

Grading

Two Exams: 40% + 40%

Lab: 20%

Minimum 80% attendance and minimum 60%marks are necessary to clear the course.


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References

Course References

Online on the Web

The Linux Documentation Project (LDP), http://www.tldp.org/

Mirror: http://www.iitk.ac.in/LDP

Red Hat Linux, O'Reilly

The course slides swill be available at http://portal.feaa.uaic.ro/Master/SDBIS/an1/la/Lists/Anunuri/DispForm.aspx?ID=14&Source=http%3A%2F%2Fportal%2Efeaa%2Euaic%2Ero%2FMaster %2FSDBIS%2Fan1%2Fla%2FPages%2Fdefault

%2Easpx

http://portal.feaa.uaic.ro/Master/SDBIS/an1/la/Lists/Anunuri/DispForm.aspx?ID=14&Source=http%3A%2F%2Fportal%2Efeaa%2Euaic%2Ero%2FMaster%2FSDBIS%2Fan1%2Fla%2FPages%2Fdefault%2Easpxhttp://www.tldp.org/http://www.tldp.org/http://www.tldp.org/


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UNIX/LINUX OPERATING SYSTEM

Introduction to Linux

Introduction to Unix

History of UNIX

What is LINUX

LINUX Distributions

Unix OS StructureUnix File System

Unix Directories, Files and Inodes

Users, Groups and Permissions


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UNIX


Unix is a multi-user, multi-taskingoperating system.

You can have many users loggedinto a system simultaneously, eachrunning many programs.

It's the kernel's job to keep eachprocess and user separate and toregula te access to systemhardware, including cpu, memory,disk and other I/O devices.


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History of UNIX


First Version was created in Bell Labs in1969.

Some of the Bell Labs programmers who hadworked on this project, Ken Thompson,Dennis Ritchie, Rudd Canaday, and DougMcIlroy designed and implemented the first

version of the Unix File System on a PDP-7along with a few utilities. It was given thename UNIX by Brian Kernighan.

00:00:00 Hours, Jan 1, 1970 is time zero for

UNIX. It is also called as epoch.


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History of UNIX


1973 Unix is re-written mostly inC, a new language developed by

Dennis Ritchie.Being written in this high-levellanguage greatly decreased theeffort needed to port it to newmachines.


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History of UNIX


1977 There were about 500 Unix sitesworld-wide.

1980 BSD 4.1 (Berkeley SoftwareDevelopment)

1983 SunOS, BSD 4.2, System V

1988 AT&T and Sun Microsystems jointly develop System V Release 4(SVR4). This later developed intoUnixWare and Solaris 2.

1991 Linux was originated.


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What is LINUX


Linux is a free Unix-type operating systemoriginally created by Linus Torvalds with theassistance of developers around the world.

It originated in 1991 as a personal project ofLinus Torvalds, a Finnish graduate student.

The Kernel version 1.0 was released in 1994and today the most recent stable version is2.6.9

Developed under the GNU General PublicLicense , the source code for Linux is freelyavailable to everyone.

http://www.linux.org/info/gnu.html


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LINUX Distributions


RedHat: http://www.redhat.com/

Fedora: http://fedora.redhat.com/

SuSE/Novell: http://www.suse.com/

Debian: http://www.debian.org/

Mandrake: http://www.mandrakesoft.com/

Red Hat Enterprise Linux is a Enterprise targetedOperating System. It based on mature Open Sourcetechnology and available at a cost with one year

Red Hat Network subscription for upgrade andsupport contract.

http://www.mandrakesoft.com/http://www.mandrakesoft.com/http://www.mandrakesoft.com/http://www.debian.org/http://www.suse.com/http://www.suse.com/http://www.suse.com/http://fedora.redhat.com/http://fedora.redhat.com/http://fedora.redhat.com/http://www.redhat.com/http://www.redhat.com/http://www.redhat.com/


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UNIX Structure



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UNIX File System



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File System


The Unix file system looks like aninverted tree structure.

You start with the root directory,denoted by /, at the top and work downthrough sub-directories underneath it.


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File System


Each node is either a file or a directoryof files, where the latter can containother files and directories.

You specify a file or directory by its pathname, either the full, or absolute, pathname or the one relative to a location.

The full path name starts with the root, /,and follows the branches of the filesystem, each separated by /, until youreach the desired file, e.g.:

/home/condron/source/xntp


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File System


A relative path name specifies the path relative toanother, usually the current working directorythat you are at. Two special directories :

. the current directory

.. the parent of the current directory

So if I'm at /home/frank and wish to specify thepath above in a relative fashion I could use:

../condron/source/xntp

This indicates that I should first go up onedirectory level, then come down through thecondron directory, followed by the source

directory and then to xntp.


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Structure of Standard Directories

in Unix/Linux


/ The ancestor of all directories on the system;all other directories are subdirectories of thisdirectory, either directly or through other

subdirectories. /bin Essential tools and other programs (orbinaries).

/dev Files representing the system's various

hardware devices. For example, you use thefile `/dev/cdrom' to access the CD!ROM drive.

/etc Miscellaneous system configuration files,startup files, etc.


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Structure of Standard Directories in

Unix/Linux


/home The home directories for all of thesystem's users.

/lib Essential system library files used bytools in `/bin'.

/proc Files that give information aboutcurrent system processes.

/root The superuser's home directory,whose username is root. (In the past, thehome directory for the superuser wassimply `/'; later, `/root' was adopted for thispurpose to reduce clutter in `/'.)


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Structure of Standard Directories in Unix/Linux


/sbin Essential system administratortools, or system binaries.

/tmp Temporary files. /usr Subdirectories with files relatedto user tools and applications.

I i i


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Directories, Files and InodesIntroduction to Linux

Every directory and file is listed in its parent

directory.

In the case of the root directory, that parent is itself.

A directory is a file that contains a table listing the

files contained within it, giving file names to the

inode numbers in the list.

The information about all the files and directories is

maintained in INODE TABLE

An Inode (Index Nodes) is an entry in the table

containing information about a file (metadata)

including file permissions, UID, GID, size, time

stamp, pointers to files data blocks on the disk etc.

I d i Li


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Users, Groups and Access Permissions


In UNIX/LINUX, there is a concept of user andan associated group

The system determines whether or not a user

or group can access a file or program basedon the permissions assigned to them.

Apart from all the users, there is a specialuser called Super User or the root which has

permission to access any file and directory

I t d ti t Li


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Access Permissions


There are three permissions for any file, directoryor application program.

The following lists the symbols used to denote

each, along with a brief description:r — Indicates that a given category of user can

read a file.

w — Indicates that a given category of user canwrite to a file.

x — Indicates that a given category of user canexecute the file.

I t d ti t Li


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Access Permissions


Each of the three permissions are assigned tothree defined categories of users.

The categories are:

owner — The owner of the file orapplication.

group — The group that owns the file or

application. others — All users with access to the

system.

I t d ti t Li


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Access Permissions


One can easily view the permissions for a fileby invoking a long format listing using thecommand ls -l.

For instance, if the user juan creates anexecutable file named test, the output of thecommand ls -l test would look like this:

-rwxrwxr-x 1 juan student 0 Sep 26 12:25 test

I t d ti t Li


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Access Permissions


The permissions for this file are listed arelisted at the start of the line, starting with rwx.

This first set of symbols define owner access.

The next set of rwx symbols define groupaccess

The last set of symbols defining accesspermitted for all other users.


I t d ti t Li


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Access Permissions


This listing indicates that the file is readable,writable, and executable by the user whoowns the file (user juan) as well as the groupowning the file (which is a group namedstudent).

The file is also world-readable and world-executable, but not world-writable.


I t d ti t Li


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Listing the Content of a DirectoryIntroduction to Linux

ls is used to list the contents of a directory.

If the command ls is written with parameter –lthen the command lists contents of theworking directory with details. Example:

$ ls –l



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Moving in DirectoriesIntroduction to Linux

cd try_itChanges the directory to try_itpwd

Prints present working directory (e.g. /home/smith/try_it)cd .. Move to superior directorypwd : Prints /home/smithcd /home The absolute path

pwd : Prints /homecd The system is returned to the user homedirectorypwd : Print /home/smith



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Make DirectoryIntroduction to Linux

The command mkdir my_dir

makes new directory my_dir (the path isgiven relative) as a subdirectory of thecurrent directory.



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Remove DirectoryIntroduction to Linux

The command rmdir your_dir

removes directory your_dir if it is empty.



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Copy FileIntroduction to Linux

The command cp file_1 file_2

copies file_1 to file_2. The both files must be inthe same working directory. If they are invarious directories, the path must be given.



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Rename and/or Move the FileIntroduction to Linux

The command mv file_1 file_2

moves file_1 to file_2

The both files must be in the same workingdirectory.

If they are in different directories, the path mustbe given.

The file_1 is removed from the disk.



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Remove FileIntroduction to Linux

The command rm file_a

removes the file_a from the system

If you use wildcard. For example

rm h*c

you will remove all files beginning with h andending with c which are in working directory.

If you writerm *

you will erase all files from your workingdirectory.


http://localhost/var/www/apps/conversion/tmp/scratch_2/?slideindex=0


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Access Permission of File/Directory


The ownership of the file or directory can bechanged using the command

chown

The group of the file or directory can be changedusing the commandchgrp

The permissions of the file can be changed usingchmod command

chmod -R ###

-R is optional and when used with directories willtraverse all the sub-directories of the targetdirectory changing ALL the permissions to ###.



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Access Permission of File/Directory


The #'s can be:0 = Nothing1 = Execute

2 = Write3 = Execute & Write (2 + 1)4 = Read5 = Execute & Read (4 + 1)6 = Read & Write (4 + 2)

7 = Execute & Read & Write (4 + 2 + 1)

RWX



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Assignment (1)Introduction to Linux

1. Login as guest (password is guest123)

2. Find the present Directory

3. Write the / directory structure

4. Write a few commands available in /bin and /sbin directory

5. Find the guest directory

6. Write the permissions of guest directory7. Create a new Directory test in guest directory

8. Write the permissions of test directory

9. Copy the file /etc/resolv.conf in test directory

10. Rename the test directory to testing

11. Delete the testing directory

12. Change the permissions of guest directory to 77513. Change the permissions of /tmp directory to 700

14. Login as root user (password is root123)

15. Change the permissions of guest directory to 700

16. The location of kernel files in Unix File System is /boot and by looking at

the kernel file, write the kernel version you are using in your system.



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Assignment (2)Introduction to Linux

1. Login as guest

2. Change directory to /

3. List the contents of /home directory

4. Find the group to which guest belongs

5. Create a file syslinus in the home area of guest (hint: use touch command)

6. Find the permissions of the file syslinus

7. Find the inode number of file syslinus (hint: ls –li)8. Copy the file syslinus to syslinus1

9. Find the inode number of file syslinus1 (hint: ls –li)

10. Move the file syslinus to syslinus2

11. Find the inode number of file syslinus2 (hint: ls –li)

12. Move syslinus2 to syslinus

13. Login as root14. Create a new user guest1 with same group as guest (hint: use GUI tool

Applications!System Settings! Users and Groups)[More on this later in the

course]

15. Create a new user guest2 with a different group than the group of guest (hint: use

GUI tool Applications!System Settings! Users and Groups)

16. Find, what permissions should the file syslinus have, so that both guest1 and guest2

Documents

Lecture1.Course Content Schedule Grading Course References Introduction to Linux